Mayors around the country are banding together and pressuring President Barack Obama to bolster protections for undocumented immigrants before he leaves office.

A coalition that includes New York City Mayor Bill de Blasio, on Thursday, sent a letter to the president urging him to "ensure continued support for vulnerable immigrants in our communities before [he leaves] office."

Other local leaders have also taken measures to protect immigrants. Suffolk Executive Steve Bellone announced in 2014 that the county's law enforcement officers would no longer cooperate with federal requests to detain undocumented immigrants unless they were presented with a warrant.

Osman Canales, of the Long Island Immigrant Students Advocates, says undocumented immigrants living in Nassau and Suffolk counties are concerned for their futures. Many fear they will be deported once President-elect Donald Trump takes office on Jan. 20.

Canales says he wants politicians like Bellone to band together with the group of mayors. The county executive's office did not immediately respond to a News 12 request for comment.

But critics say the incoming president should be able to institute his own policies without any last-minute changes from the current administration.