The NYPD has mobilized busloads of officers, who are standing by to clear Columbia anti-Israel protesters, but the university has not asked for cops, according to sources.

Hundreds of students and faculty members defied the 2 p.m. Monday deadline to vacate a tent camp on the campus — marching, singing, chanting and playing drums at the Ivy League university.

Patrol officers have been mobilized on Randall’s Island, just a few miles from Columbia’s Morningside Heights campus, police sources told The Post.

The NYPD’s Strategic Response Group is not part of the mobilization, sources said.

Cops can’t enter the campus unless Columbia administration asks for assistance.

On April 18, when the protest was just starting out, embattled Columbia President Minouche Shafik called in police to break up the encampment.

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More than 100 protesters were cuffed and hauled away by cops, but the tent city was quickly reestablished after cops left and has remained ever since.

However, so far this time around no such order has been given, and hundreds of demonstrators remain on the Ivy League campus even after today’s deadline came and went.

In an open letter on Monday morning, Shafik said that the university would use “internal options to end this crisis as soon as possible.”

Shafik faced strong criticism from faculty and other members of the Columbia community over her use of NYPD cops to break up the tent camp earlier this month.