The White House stepped up travel restrictions, banning all travel from Iran and the entry of any foreign nationals who visited the country in the past 14 days, as it introduced measures to restrict the spread of the coronavirus.

Vice President Mike Pence announced on Saturday fresh warnings on travel to specific regions of Italy and South Korea, even as President Trump urged the public not to panic.

In the White House briefing room, Trump also announced he would meet the heads of the world's biggest pharmaceutical companies on Monday to discuss progress on a vaccine and said he was considering closing the southern border with Mexico.

"We have received a lot of power on the southern border from the courts, but we are looking at that very strongly," he said.

He spoke minutes after officials in Washington state announced the first death on American soil of a coronavirus patient.

Trump paid tribute to a "wonderful woman" in her 50s who was "a medically high-risk patient," but he assured people there was no need to panic.

"But healthy individuals should be able to fully recover," he said.

The Centers for Disease Control and Prevention later acknowledged that it had "erroneously identified the patient as a female" at the briefing.

Pence, who is in charge of the administration's response to the virus, met health officials in the situation room on Saturday morning.

Since the early stages of the COVID-19 outbreak, which has been traced to Wuhan, China, the administration said it has taken an aggressive approach to confront the spread of this disease. "We moved very early," said Trump, stating that his early travel ban on China slowed the spread of the virus to the United States.

It marked the president's second visit to the briefing room in four days as he tries to demonstrate a firm hand at the center of the response to COVID-19. Aides have been spooked by precipitous market plunges at a time when they want a booming economy at the heart of their reelection push.

A day earlier, he angered public health experts by accusing his opponents of politicizing the outbreak and told his supporters to treat the coronavirus warnings as if they were a hoax.

“They tried the impeachment hoax ... this is their new hoax," he said at a rally in North Charleston, South Carolina.

It followed comments by his acting chief of staff, Mick Mulvaney, that opponents in the media were hoping the virus would bring down Trump.

Meanwhile, the crisis is growing around the world.

Deaths in Iran from the virus reached 43, the highest outside China, while the number of infected people rose to 593, according to a health official. And in Italy, the number of deaths rose to 29 with 1,128 cases in total.

Around the world, more than 85,000 people have contracted the virus.