The US Department of Education on Monday froze more than US$2 billion in federal funding for Harvard University, just hours after the school rejected US President Donald Trump's demands that it make deep policy changes on diversity.

A Department of Education task force on combating anti-semitism said in a statement that it was freezing US$2.2 billion in multi-year grants and US$60 million in multi-year contract value to Harvard University.

The move marks a new level of contentiousness between the Trump administration and American universities.

The Trump administration has frozen hundreds of millions of dollars in federal funding for numerous universities, pressing the institutions to make policy and other changes and citing what it says is a failure to fight anti-semitism on campus.

Deportation proceedings have begun against some detained foreign students who took part in pro-Palestinian demonstrations, while visas for hundreds of other students have been cancelled. The crackdown has raised concerns about speech and academic freedoms.

Harvard on Monday rejected Trump administration demands that to receive federal funding it end diversity efforts and take other steps that the university said would stifle intellectual freedoms of faculty and students. (Reuters)