New York City Mayor Bill de Blasio weighed in Monday on a dispute Hillary Clinton and Bernie Sanders are having over the scheduling of a Democratic debate in New York ahead of its primary this month.

On Twitter, de Blasio endorsed the idea of an April 14 debate that NY1 News and CNN have proposed and that Clinton has agreed to. Sanders' campaign suggested Sunday that that date isn't doable because of a New York City rally it has already scheduled for that day. De Blasio said he would get Sanders whatever permit he needs so that he could also hold his rally.

Let's make @NY1 4/14 BKLYN debate happen. @BernieSanders: I'll help you secure any permit you need to ensure your NYC rally can happen too. — Bill de Blasio (@BilldeBlasio) April 4, 2016

De Blasio, of course, is a surrogate for Clinton's campaign and formally endorsed her last October. He served as Clinton's campaign manager for her successful 2000 Senate bid.

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In separate interviews on Sunday, Clinton told both NY1 News and ABC News' "Good Morning America" that she would be willing to attend either of their proposed New York debates.

"I'll be there," the Democratic candidate said to each news outlet.

The NY1 News debate has been tentatively scheduled for April 14, which is five days before the state's primary on April 19. Asked if he's available for that debate on CNN's "State of the Union," Sanders said he wasn't sure yet.

"I'm not quite sure how that works on our schedule. We may have a major rally being scheduled. We have been talking, I think, to NBC and to CNN, and we're working on a number of dates. First, I'm very glad that the secretary has accepted the challenge to debate in New York. I think we can work out a date that works for her schedule, that works for my schedule," said the independent senator who has been pushing for a debate in Brooklyn.

Later in the day, Sanders' campaign spokesman Michael Briggs released a statement that said Sanders has accepted an invitation from NBC News for a debate on April 10.

"The April 10 debate date is one of four dates that the Sanders campaign had proposed for a debate with Secretary Clinton before the New York primary election. He is available on April 10, 11, 12 or 13. He looks forward to a debate on any of those days," he said.

Clinton campaign spokesman Brian Fallon tweeted that Sanders had originally asked for an April 14 debate and he suggested that Sanders is not compromising.

Sen Sanders requested a debate in Brooklyn on April 14. We have agreed to a debate in Brooklyn on April 14. Not sure what the issue is. — Brian Fallon (@brianefallon) April 3, 2016

We are at the point that if we agreed to a debate in Williamsburg, they'd say Bushwick. If we said Gowanus, they'd demand Park Slope. — Brian Fallon (@brianefallon) April 3, 2016