EXCLUSIVE: Brooklyn Councilman Ari Kagan expected to switch parties from Democrat to GOP

Brooklyn Councilman Ari Kagan is expected to switch his party affiliation from Democrat to Republican on Monday — and announce a general election challenge against one of his Democratic colleagues next year — three sources familiar with the matter told the Daily News.

Kagan, who was first elected in 2021 to represent Coney Island and other southern Brooklyn neighborhoods, is set to officially declare he’s becoming a Republican during an afternoon press conference at City Hall, said the sources, who spoke on condition of anonymity.

As a Republican, Kagan plans to challenge Brooklyn Councilman Justin Brannan, a longtime member who serves as the Council’s Finance Committee chairman, according to the sources. Next year’s Council elections are Nov. 7.

Kagan declined to comment Sunday night, saying, “I will prefer to discuss it tomorrow.”

Asked whether he is changing parties in order to challenge Brannan, make a political statement or both, he said, “It’s everything — let’s talk tomorrow.”

Brannan blasted Kagan’s expected move.

“Frankly, I’m embarrassed for him,” he said. “This is just desperate and sad. When you stand for nothing, you’ll fall for anything.”

Kagan’s unusual party switch comes after this year’s Council redistricting process effectively pushed him out of his current district.

A Democratic insider expressed disbelief that Kagan would align himself with the GOP since its conference leader, Staten Island Councilman Joe Borelli, played a key role in finalizing the new district borders.

“He makes a puzzling and hypocritical move to the very party that screwed him on redistricting,” the source said of Kagan.