By Jonathan Allen

(Reuters) - Hillary Clinton agreed on Thursday to some of the terms laid down by an opponent, Senator Bernie Sanders, in his call to increase the number of public debates as they vie to become the Democratic candidate in November's U.S. presidential election.

Clinton's two main Democratic challengers, Sanders and former Maryland Governor Martin O'Malley, have long called for more debates. They have complained that the relatively skimpy schedule of only six encounters was designed by the party to protect Clinton's position at the top of opinion polls.

But the call for more debates intensified this week after a hastily arranged debate next Thursday in New Hampshire was announced, organized by a news channel and a state newspaper. Both Clinton and O'Malley said they would attend if all the candidates agreed, despite risking the ire of the Democratic National Committee, which has forbidden candidates from taking part in unsanctioned encounters.

On Wednesday evening, the Sanders campaign called for three more debates, in March, April and May. The campaign also stipulated that none be held on a Friday, Saturday or holiday weekend, when the number of potential viewers typically dips.

If Clinton would commit to this, his campaign said, then Sanders would also agree to join Clinton and O'Malley at the Feb. 4 debate convened by MSNBC and the New Hampshire Union Leader newspaper, just days before the state becomes the second in the country to vote for Republican and Democratic presidential candidates.

"Senator Sanders is happy to have more debates, but we are not going to schedule them on an ad hoc basis at the whim of the Clinton campaign," Sanders' campaign manager, Jeff Weaver, said in a statement. Weaver said Clinton had only agreed to next week's debate because Sanders has been gaining on her in polls.

The response from the Clinton camp on Thursday acceded to some of these conditions, saying it would discuss adding debates only in April and May.

"We have always been willing to add additional debates beyond the six that had been scheduled and look forward to starting discussions on scheduling debates in April and May," Clinton spokesman Brian Fallon said in an email to reporters.

Spokesmen for Clinton and Sanders did not respond to emails asking if the two campaigns were now in agreement.

It remains unclear if any additional debates will come to pass. The Democratic National Committee has said it will not sanction the debate organized for next week, though it seems unlikely it will ban all three candidates from the remaining two sanctioned debates.

(Reporting by Jonathan Allen; Editing by Jonathan Oatis)

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