US President Donald Trump insisted Tuesday that Harvard, the world's wealthiest university, pay back millions it received under a massive government stimulus package meant to cushion the economy from the coronavirus pandemic.

"Harvard, you pay that money back. I want Harvard to pay the money back, ok? And if they don't do that, then we'll do something else," Trump said at his daily briefing on the pandemic.

"I don't like it at all. This is meant for workers. This isn't meant for one of the richest institutions ... in the world," the billionaire president continued.

Shortly after Trump spoke, the Cambridge, Massachusetts-based university tweeted that it was allocated $8.6 million as part of the historic $2.2 trillion package passed last month to stimulate the collapsing US economy.

It said 100 percent of the funds would be given to students "facing urgent financial needs due to the COVID-19 pandemic", and stressed that the money did not fall under the Paycheck Protection Program for small business relief.

"President Trump is right that it would not have been appropriate for our institution to receive funds that were designated for struggling small businesses," it tweeted.

A Harvard student sits with her belongings before returning home on March 12, 2020, as students left campus due to the coronavirus pandemic
A Harvard student sits with her belongings before returning home on March 12, 2020, as students left campus due to the coronavirus pandemic GETTY IMAGES NORTH AMERICA / Maddie Meyer

It did not respond directly to Trump's call for the money to be repaid.

"Give it back. Everyone, literally everyone, needs it more than you," responded one user, Ellen Sledge.

The university has been under fire for a day already over the funds.

"The last time Harvard got this much money out of the blue, they had to accept Jared Kushner," joked Comedy Central's The Daily Show on Twitter, referring to Trump's son-in-law, on Monday.

The Department of Education was to receive $30.8 billion to support schools and universities, which are closed across the country, under the stimulus package.

The Harvard Crimson reported Tuesday that the university's endowment, the largest of any in the world, was last valued in 2019 at $40.9 billion -- though it cited administrators as saying that may have declined to the "mid 30-billion range" as a result of the coronavirus pandemic.

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