Massachusetts Representative Barney Frank on Tuesday defended describing gay Republicans as “Uncle Toms.”

The openly gay 72-year-old Frank, who is not seeking re-election, first made the assertion during an appearance on SiriusXM's The Michelangelo Signorile Show and then repeated the claim as he participated in a panel program of the LGBT Caucus at the Democratic National Convention (DNC).

“When they tell us that they're happy to be Republicans because they're getting acceptance and civility, I gotta say that I am again inclined to think that they're called Log Cabin club because their role model is Uncle Tom,” Frank said.

In a statement, Frank expanded on what he described as “very harsh criticism.”

“[M]y use of 'Uncle Tom' was based not simply on this awful fact that they have chosen to be actively on the wrong side of an election that will have an enormous impact on our right to equality,” he wrote.

Log Cabin Republicans “may mislead people who do not share their view that tax cuts for the wealthy are more important than LGBT rights into thinking that they are somehow helping the latter by supporting Mitt Romney and his Rick Santorum platform.”

Frank charged that the group had failed to influence other Republicans to support gay rights, and yet, “they pretend to be successful … and urge people to join them in rewarding the Republicans when they have in fact continued their anti-LGBT stance.”

“Some have complained that in comparing the Log Cabin Republicans to Uncle Tom, I was ignoring the fact that they are nice,” Frank offered in conclusion. “I accept the fact that many of them are nice – so was Uncle Tom – but in both cases they've been nice to the wrong people.”

R. Clarke Cooper, executive director of Log Cabin Republicans, responded to Frank's missive in a statement released to POLITICO.com.

“Congressman Frank, of all people, should understand the importance of perseverance when working within a party to achieve change – after all, it was not so long ago his party was indifferent at best when it came to respecting gay families,” Cooper said. “Leaders committed to LGBT equality know that every victory our community has achieved has required bipartisan advocacy and bipartisan votes, and winning support from Republicans will only be more important in the days ahead.”

“Come January, Republicans will maintain a majority in the House and likely secure a majority in the Senate. Without Log Cabin Republicans working with fellow conservatives, LGBT Americans would be left without a credible voice within the GOP. Barney Frank's denial of Log Cabin Republicans success, particularly on 'Don't Ask, Don't Tell' repeal and the freedom to marry in New York, is sad but unsurprising. It is time for him to pass on the baton to leaders better suited to a world where equality is not a partisan issue.”