Mayor Mamdani and President Trump plan to meet in Gracie Mansion Monday, as world leaders gather in New York for the United Nations General Assembly — marking the latest episode in the unusually friendly odd-couple relationship between the two polar-opposite pols.

City Hall confirmed the meeting Sunday, saying in a statement, “The meeting will focus on issues affecting New York City and New Yorkers.”

After Mamdani’s primary win last June, the president blasted him as a “100% Communist Lunatic” in a Truth Social post. But since Mamdani took office, the two men have mostly publicly gotten along.

“I speak to him a lot,” the president said at this year’s State of the Union address. “Bad policy, but nice guy.”

In February, Mamdani presented Trump with a charm-offensive pitch to build 12,000 housing units in New York City at a White House sit-down, posing with a grinning Trump as he clutched a mock Daily News front page given to him by the mayor.

The paper, which read, “Trump to City: Let’s Build,” was a play on The News’ iconic “Ford to City: Drop Dead” front page from 1975.

Despite the chumminess, Mamdani and Trump have clashed on policy, with the mayor last week suing the White House, along with Attorney General Tish James, to block the administration’s plan to put green cards out of reach for immigrants who use public benefits.