Vice President Mike Pence tried to downplay confusion caused by Donald Trump's speech on the coronavirus outbreak that left more unanswered questions than calm.

"I don't think there was confusion," Mr Pence told CNN as he was deployed to make the morning television rounds to defend the president's speech and the policies he unveiled during a rare primetime address from the Oval Office.

Mr Trump criticised European Union officials for, according to him, being too slow in their response to the novel virus. That came as he announced he was cutting off travel to anyone from a long list of European countries for 30 days starting Friday -- but the president did not explain well that US citizens and permanent residents would be exempt but subject to virus testing.

Nor did the president make any attempt to explain how Americans and permanent residents would get back to the United States. That was up to his ever-loyal No. 2.

"Americans coming home will be funelled through 13 different airports," Mr Pence said Thursday morning. "They'll be screened and then we're going to ask every American and legal resident returning to the United States to self-quarantine for 14 days."

Mr Trump flubbed several parts of his speech, including adding "only" to a section about EU cargo from transatlantic trade also being exempted. The president quickly had to clarify in a late-night tweet, writing it is "very important for all countries & businesses to know that trade will in no way be affected by the 30-day restriction on travel from Europe. The restriction stops people not goods."

US stock markets were not calmed by Mr Trump's speech, with the Dow Jones Industrial Average falling by 1,700 points as it opened, triggering the second temporary pause in trading of the week.