With few regrets and a few more parting quips, Rep. Barney Frank of Massachusetts announced Monday that he will retire at the end of the current congressional term.

Congressman Frank, the longest-serving openly gay member of Congress and one of four openly gay congressional members currently in office, told reporters at a news conference in Newton, Mass., that his decision not to run for reelection in 2012 was driven in part by the realities of redistricting as well as his desire to pursue writing and teaching. His announcement was met with an outpouring of gratitude by LGBT organizations who praised his gay rights legislative work and his influence on a new generation of LGBT political leaders.

Frank's fourth congressional district now includes more conservative areas of Massachusetts as well as thousands of new constituents, so a race would require significant campaigning and fund-raising that Frank is unwilling to do. The 71-year-old representative has previously said he would not remain in office past the age of 75, though Frank had announced in February that he would run for a final reelection bid next year.

In a Monday statement, President Barack Obama called Frank "a fierce advocate for the people of Massachusetts and Americans everywhere who needed a voice."

"He has worked tirelessly on behalf of families and businesses and helped make housing more affordable. He has stood up for the rights of LGBT Americans and fought to end discrimination against them," Obama said.

Frank told reporters Monday not to expect a quiet exit from the political arena, however. "I'm not retiring from advocacy of public policy. I think I will have more impact in some areas not [being] in office," Frank said. In his post-public official role, "I think I will find my motives less impugned, and I'll be able to talk about the merits" of issues important to him, he said.

The current ranking member on the House Financial Services Committee, Frank immediately shot down any notion that he would parlay his congressional tenure into a K Street position. "I will be neither a lobbyist nor a historian. There's no way I would be a lobbyist," he said. "I will miss this job and will have tinges of regret. ... But one of the advantages of not running for office is that I don't have to pretend to be nice to people I don't like."

Frank is the second LGBT congressional member not seeking reelection for a House seat next year. Rep. Tammy Baldwin, who was first elected to represent Wisconsin's second congressional district in 1998, is now running to fill retiring U.S. senator Herb Kohl's seat. The other openly gay members of Congress are David Cicilline of Rhode Island and Jared Polis of Colorado.

"Barney's legacy will be huge, but he had shared recently with friends his frustrations with getting anything done now in Washington and that his last reelection seemed to take a heavy toll," said one source.

In a statement, Congressman Polis said, "Barney Frank was a groundbreaking pioneer and one of the most insightful, knowledgeable and humorous people ever to grace the halls of Congress. We will miss his leadership on a wide range of issues -- from fighting to rein in Wall Street's excesses and working to stabilize our economy to standing up for equal rights for LGBT Americans and curtailing runaway Pentagon spending. Congressman Frank championed the rights of all Americans, the economic security of all of our families, and a politics of inclusion and hope. It's a great loss for the Congress but Barney leaves behind an enviable record of accomplishment. I will miss his presence every day."

The first openly gay member of Congress to come out voluntarily, Frank's office has also left its mark on LGBT firsts, with senior legislative assistant Diego Sanchez becoming the first openly transgender Hill staffer in 2009.

Frank created friction with transgender advocates in 2007 when he decided to support a version of the Employment Non-Discrimination Act that included protections for sexual orientation but not gender identity, arguing that an inclusive ENDA was not politically viable. He said it would have been a "mistake" to push for gender identity protections at that time and urged passage of a sexual orientation-only version of the bill, with a second ENDA bill later to address gender identity. Frank now fully supports an inclusive ENDA, and the National Center for Transgender Equality praised him in a statement on Monday.

"While the relationship between Congressman Frank and transgender people has not always been smooth, the truth is that he has pushed very hard for trans rights in Congress and the administration over the last few years," said executive director Mara Keisling.

"Social justice work is largely about winning people to our side," the statement continued. "As they become stronger allies, we have a moral and commonsense obligation to embrace them and acknowledge their good work. The effort and influence he has exerted for trans people has mattered and has moved us down the field. It will be somewhat harder to advance our cause in Congress with the congressman gone, but justice will be won for trans, gay and bi people and Congressman Frank will have been a very important part of that."

Frank, the highest-ranking openly gay member of Congress, came out after the late Gerry Studds of Massachusetts. Studds was forced to come out in 1983 when he was censured by the House for an affair 10 years earlier with a 17-year-old congressional page. Studds went on to win reelection.

Human Rights Campaign president Joe Solmonese, a Massachusetts native who worked on one of Frank's first congressional campaigns, issued a statement Monday morning.

"Barney Frank has exemplified true leadership over his more than 30 years in the U.S. House of Representatives," he said, citing passage of "don't ask, don't tell" repeal and hate-crimes legislation as key examples. "But it goes beyond that. His service as chairman of the House Financial Services Committee during a time of great economic upheaval made a gay man one of the most powerful people in the country and he used that power for great good. America, Massachusetts, and LGBT people are better off for Barney Frank's service."

Chuck Wolfe, president and CEO of the Gay and Lesbian Victory Fund, said, "Barney Frank's political career may be coming to an end, but his legacy will outlive us all. His decision to come out as gay more than two decades ago gave LGBT Americans an authentic voice and a persistent champion in Washington. He has used that voice loudly and often, speaking personally, humorously and effectively about the hopes and challenges of Americans who are lesbian, gay, bisexual, or transgender. We will miss that voice very much."

"The good news is that Congressman Frank has also inspired a new generation of LGBT leaders who are following in his footsteps and choosing to serve in public office openly, honestly, and unafraid to be themselves," Wolfe continued. "More than simply inspiring them, he has helped them run and win, and he has been an enormously supportive and generous friend to the Victory Fund."

A founder of the Stonewall Democrats, Frank "blazed a trail for the LGBT community in many ways -- most especially for the openly gay representatives who followed him into the halls of Congress," said Jerame Davis, the organization's new executive director.

Of Frank's impending retirement, Davis said, "He'd be well within his rights to say, 'I need to spend time with my partner and live my life now.' But I don't see Barney Frank being the type of guy who does that. I see him staying involved in some way, though I'm not sure what that's going to look like."

Among the legislative regrets Frank mentioned in response to a reporter's question was his vote against a resolution authorizing the first Gulf War in 1991. He also said he would like to debate former House speaker Newt Gingrich, the latest front-runner in the Republican presidential nomination race, on the Defense of Marriage Act to determine who exactly is the primary threat to the sanctity of marriage.

After the jump, Representative Frank's full written statement on his decision not to run for reelection in 2012.

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Frank's full written statement:

I will not be a candidate for reelection to the House of Representatives in 2012.

I began to think about retirement last year, as we were completing passage of the financial reform bill. I have enjoyed -- indeed been enormously honored -- by the chance to represent others in Congress and the State Legislature, but there are other things I hope to do before my career ends. Specifically, I have for several years been thinking about writing, and while there are people who are able to combine serious writing with full-time jobs, my susceptibility to distraction when faced with a blank screen makes that impossible.

In 2010, after the bill was signed into law, I had tentatively decided to make this my last term. The end of next year will mark 40 years during which time I have held elected office and a period of 45 years since I first went to work in government full time as an aide to Mayor Kevin White in late 1967.

But with the election of a conservative majority in the House, I decided that my commitment to the public policies for which I have fought for 45 years required me to run for one more term. I was -- and am -- concerned about right-wing assaults on the financial reform bill, especially since we are now in a very critical period when the bill is in the process of implementation. In addition, recognizing that there is a need for us to do long-term deficit reduction, I was -- and am -- determined to do everything possible to make sure that substantial reduction in our excessive overseas military commitments forms a significant part of the savings over the next 10 years.

But, my concern for these two issues today cuts very much in the opposite direction -- namely, in favor of forgoing a year-long full-time election campaign and instead focusing the next year on those two issues in Congress.

Two factors lead me to this view. The newly configured district contains approximately 325,000 new constituents, many of them in a region of the state that is wholly new to me as a Member of Congress. A significant number of others are in the area along our east-west border with Rhode Island which I have not represented for 20 years. This means that running for reelection will require -- appropriately in our democracy -- a significant commitment of my time and energy, introducing myself to hundreds of thousands of new constituents, learning about the regional and local issues of concern to them and, not least importantly, raising an additional 1.5 to 2 million dollars.

This would compete with two other obligations which I neither want to nor can avoid. First, I will continue to represent hundreds of thousands of people in the current 4th District to whom I am committed as the person they voted for a year ago. I have acquired a strong attachment to many of the people and causes I have worked with here. The Congressional redistricting removes from the district I represent virtually the entire fishing industry of Southeastern Massachusetts. It very substantially reduces the number of Azorean-Americans I will represent, and again removes almost completely people of Cape Verdean ancestry. Introducing myself and learning about the new area while continuing to give the existing area the full representation it deserves would make demands of my time that would detract from my focus on the national issues.

There is another, equally important consequence of the fact that so many of the people in this district would be new constituents that help persuade me to announce my retirement. The obligation of a Member of Congress to work as an advocate for the people he represents on local and regional issues that require or involve Federal government response are of paramount importance. And I am proud of the work I have done in that regard for the people I have been privileged to represent over these years. But as in almost every case, where there were significant local or regional issues involving environmental matters, transportation matters, housing matters etc., it took more than two years to resolve them. The relevance is that running again for one more term, I would be asking 325,000 new constituents to give me the mandate to be their advocate with the federal government for only two years. Starting on a series of projects only to be passing them along in various stages of incompletion to a successor two years later is not a responsible way to act.

There is one other factor that influenced my decision as I went through this year. Our politics has evolved in a way that makes it harder to get anything done at the federal level. I believe that I have been effective as a Member of Congress working inside the process to influence public policy in the ways that I think are important. But I now believe that there is more to be done trying to change things from outside than by working within. I am announcing today my retirement from elected office after 40 years but not my retirement from public policy advocacy and given the nature of our current situation, in some ways I believe I may have more impact speaking, writing and in other ways advocating for the changes that I think are necessary than trying to bring them about inside our constricting political process.

In summary, I am required to choose. I have to choose between fulfilling my obligation as a ranking member of the Financial Services Committee on behalf of financial reform and my responsibility to continue to be a full representative of the people who voted for me in 2010, and on the other hand to engage in a full-fledged Congressional campaign in a district which is very different than the current one. I am also required to choose between concentrating my efforts on trying to change the political equation in the country over the next year and doing the best I can within the conflicts and restrictions of the current set of forces. Given this, I am going to do what Massachusetts politicians often do, quote a former President from Massachusetts, although not the one usually cited. I do not choose to run for reelection in 2012.