Trump has not specified how he would end federal funding to these cities.
The plan could affect many municipalities across the nation, including some of the country’s largest cities.
Bill DeBlasio, mayor of New York City, has been a vocal defender of sanctuary cities since the election.
“If the federal government wants our police officers to tear immigrant families apart, we will refuse to do it,” DeBlasio said in a speech Nov. 21.
Laws banning police officers from asking for immigration status were designed to allow undocumented immigrants to interact with police without fear of deportation, said Alex Nowrasteh, an immigration policy analyst at the Cato Institute, a Libertarian think tank.
Although sanctuary city laws have become more politicized in recent years, he said they are supported by police and have economic benefits.
“It allows (undocumented immigrants) to be more economically active, to travel more freely and to not fear interactions so much with the local or city governments and their jurisdictions,” he said.
But sanctuary cities are operating outside of their legal boundaries, said Ron Woodard, the director of NC LISTEN, an organization advocating stronger immigration control.