New York City Mayor Eric Adams appears open to switching parties to become a Republican, as he declined to rule out a future change in political allegiances during a pair of interviews Friday that came as he has increasing warmed to President-elect Donald Trump.

The comments from Adams, the top Democrat in one of the country’s most liberal cities, riled critics who have grown concerned over the mayor’s increasing willingness to throw his support behind Trump and his hardline immigration policies.

Adams, who faces federal corruption charges, was a registered Republican in the 1990s and early 2000s but has spent his political career as a Democrat.