Earlier today, President Trump said he was considering imposing a quarantine on New York, and parts of New Jersey and Connecticut, to slow the spread of coronavirus.

New York Governor Andrew Cuomo has responded by saying that the "quarantine" is already happening in his state, which has banned major gatherings and ordered people to remain at home. However, Mr Cuomo said he would oppose any effort to "lockdown" his state.

"If you said we were geographically restricted from leaving, that would be a lockdown," he told CNN.

"Then we would be Wuhan, China, and that wouldn’t make any sense," he said, adding that this would cause the stock market to crash in a way that would make it impossible for the US economy to "recover for months, if not years".

"You would paralyse the financial sector," he added, calling it the opposite of Mr Trump's hope to quickly jumpstart the US economy.

"It's a preposterous idea, frankly," he said, adding it would be "anti-American" and a "declaration of war" on states by the federal government.

It is not clear whether Mr Trump could close state borders. While the president does have sweeping powers, especially during a national emergency, it is the role of state and local governments to take the lead in preventing the spread of disease.

Mr Cuomo also said that he plans to sue Rhode Island if they continue targeting New Yorkers to threaten them with punishment if they do not quarantine. That state's governor has mobilised soldiers to seek out fleeing New Yorkers.