Harvard University expanded its lawsuit Tuesday against the Trump administration for freezing billions of dollars in federal funds, ratcheting up the high-stakes legal battle between the wealthiest US university and the White House.

Harvard University expanded its lawsuit challenging the Trump administration's moves to cut off billions of dollars in federal funding to the Ivy League school on Tuesday after officials said they are terminating an additional $450 million in grants.

The university expanded its ongoing suit after the Trump administration said it would stop issuing grants to the school and promised to take another $450 million.