Tensions are rising across American academia as the Trump administration froze over $2 billion in multi-year grants and contracts at Harvard University after its leaders refused to make key policy changes the White House also is demanding of other elite US colleges.

U.S. President Donald Trump threatened to strip Harvard of its tax-exempt status on Tuesday and said the university should apologize, a day after it rejected what it called unlawful demands to overhaul academic programs or lose federal grants.

Harvard University was hit with a $2.2 billion federal funding freeze after rejecting a list of sweeping demands from The Trump administration. MSNBC’s Ari Melber reports. (The Beat's YouTube playlist