NEW YORK (Reuters) - Hillary Clinton continued to resist calls to release her transcripts of paid speeches she gave to Goldman Sachs and other banks, saying she would hold onto them until Bernie Sanders and other rivals for the U.S. presidency released theirs.

U.S. Democratic presidential candidate Hillary Clinton speaks at a campaign rally at the Laborers International Union hall in Las Vegas, Nevada February 18, 2016. REUTERS/David Becker

Sanders, her populist rival for the Democratic presidential nomination who has surged in polls with his furious rebukes of Wall Street and its role in the 2008 recession, said on Friday he had none to release because he does not give paid speeches to banks.

Clinton’s reluctance to reveal what she privately told banks and other organizations has become an increasingly heated issue ahead of the election this November as she fights suggestions by Sanders and others from their party’s more liberal wing that she is too cozy with the U.S. financial industry.

“I am happy to release anything I have whenever everybody else does the same, because everybody in this race, including Senator Sanders, has given speeches to private groups,” she said on Thursday night in a televised ‘town hall’ event with voters in Nevada. Nevada is the third state to vote for the Democratic Party’s nominee in caucuses to be held on Saturday.

Clinton has earned more than $20 million for 92 paid speeches since leaving her job as U.S. secretary of state in 2013, according to records disclosed by her campaign, including $675,000 for three closed-door speeches to New York-based investment bank Goldman Sachs. Her husband, Bill Clinton, has earned even more since he stepped down as president in 2001. She says this income has no influence on her policies and that she would increase Wall Street regulation.

Sanders, a U.S. senator from Vermont, last gave a paid speech in 2004, according to his Senate financial disclosures, when he spoke about social activism at the California Institute of Technology in an event that was open to the public. He earned $2,000, according to his disclosures.

On Friday, Sanders’ spokesman said the senator “accepts Clinton’s challenge.”

“He will release all of the transcripts of all of his Wall Street speeches,” Michael Briggs said in a statement. “That’s easy. The fact is, there weren’t any.”

Briggs said he hoped this was sufficient for Clinton to release her transcripts. Clinton’s standard speaker’s contract stipulated that the speech’s host make a transcript that would then remain in Clinton’s control.

Spokesmen for Clinton and Goldman Sachs did not respond to questions.

It remained unclear if Clinton’s Republican rivals would meet her demands.