U.S. President Donald Trump said on Friday his administration will revoke Harvard University's tax-exempt status, returning to a threat he issued against the Massachusetts school last month as part of his wider attack on elite universities.

Trump is targeting Harvard "for blatantly political purposes," U.S. Sens. Elizabeth Warren and Ed Markey, D-Mass., said Friday.

A New York University School of Law professor on tax policy, called the news a “lawless action by the President.”