The US state department has urged all Americans to return from abroad, as the government raised its travel advisory to four, a level typically reserved for travel to war-torn countries.
In an advisory, the state department said US citizens who live in the United States "should arrange for immediate return to the United States, unless they are prepared to remain abroad for an indefinite period".
President Trump said he was considering deploying the military to help American citizens return home amid reports of thousands stranded across the world.
The push to repatriate Americans came as the number of cases in the United States continued to rise, with two members of Congress confirming they have tested positive for the disease.
Ben McAdams, a Democratic congressman from Utah, and Mario Diaz-Balart, a Republican representative from Miami, have both contracted Covid-19 and are in isolation.
The number of cases in the United States had passed 11,000 as of Thursday evening, with New York alone reporting a climb of more than 1,000 cases since Tuesday.
Mr Trump and vice-president Mike Pence held a teleconference call with governors across the country on Thursday, as individual states continue to take action to combat the spread of the virus.
Reported cases of the virus are now in all 50 states in addition to Washington DC. Governors reported problems with testing and capacity at their hospitals. Others requested block grants from the government to help with the crisis.
Earlier, the president announced that the Food and Drug Administration (FDA) had approved the use of anti-malarial drug chloroquine which is also given to arthritis patients, to treat coronavirus. A second drug, remdesivir, would also become available to patients soon, he said.
But while Mr Trump said people would be using the drug "literally within a few days", the head of the FDA, Stephen Hahn, questioned that timing.
“I want to assure you we’re working as quickly as we can, I don’t want to speculate about a timeline,” he said, adding that the FDA was “looking at everything that’s coming across our desks as possible treatment options for coronavirus”.
Mr Trump defended his handling of the crisis during the daily coronavirus task force briefing.
New rules
“Nobody in their wildest dreams would’ve ever thought we needed tens of thousands of ventilators,” he said.
“We were very prepared . . . The only thing we weren’t prepared for was the media. The media has not treated it fairly,” he added.
He also repeated his description of Covid-19 as the “Chinese virus”, defending his use of the term.
Meanwhile, the US economy continued to buckle under the strain of the growing crisis. New figures showed a 70,000 increase in unemployment claims last week.
Retail outlets, restaurants, and service industries across the country have closed as states have introduced stringent new rules to combat the spread of the virus. Car manufacturers including Ford and General Motors have temporarily closed factories, as supply chains have been hit.
US stock markets remained highly volatile on Thursday, though regained some ground by the close of session, following commitments by the Federal Reserve and the European Central Bank overnight.
The US Senate was locked in discussion on Capitol Hill about the contours of a third coronavirus-related Bill this month to help tackle the crisis. It includes a proposal by the White House to give up to $500 billion in direct payments to Americans in two tranches. A rescue package for the airline sector is also under discussion as well as proposals to help small businesses.
