Massachusetts Representative Barney Frank is not backing down from his remarks that this weekend's gay march on Washington is “a waste of time at best.”

Frank, the nation's most powerful openly gay elected official, criticized the effort a second time in less than a week.

On Tuesday, he said on the Michelangelo Signorile radio show: “I literally don't understand how this will do anything. People are kidding themselves. I don't want people patting themselves on the back for doing something that is useless. Barack Obama does not need the pressure.”

Thousands of gay activists are expected to descend on Washington to press Congress – and the president – for action on gay rights legislation at Sunday's National Equality March. Organizers say they are disillusioned with the new administration's sluggish pace on gay and lesbian rights.

There is no word that President Obama has accepted an invitation to speak at the march.

The president renewed his promise to end the military's ban on open gay service in a speech to 3,000 gay activists at Saturday's Human Rights Campaign (HRC) fundraiser in Washington.

“I will end 'don't ask, don't tell',” Obama told a cheering crowd. “That is my commitment to you.”

Protesters outside the Walter E. Washington Convention Center held up banners urging the president to live up to his campaign promises.

In an interview Friday with The Associated Press, Frank called the march “an emotional release.”

“The only thing they're going to be putting pressure on is the grass,” he said.

Frank urged protesters to lobby their elected officials in place of marching, adding that most lawmakers having returned home for the holiday weekend would not hear their protests.

“Call or write your representative or senator, and then have your friends call and write their representative or senator,” Frank said. “That's what the NRA does. That's what the AARP does.”