Health officials in the state of Washington reported the first coronavirus death in the U.S. on Saturday, as the White House imposed additional international travel restrictions.

Vice President Mike Pence, head of the government’s task force on the virus, said at a briefing that the U.S. will bar foreign nationals who have traveled to Iran in the past 14 days. The government is also strongly advising people against travel to areas in Italy and South Korea that are affected by the virus and has asked those countries to ensure adequate screening of travelers to the U.S.

At the hastily arranged White House news conference, President Trump and other officials sought to project confidence in how the U.S. is handling the situation, which has sent markets tumbling. “This too will end,” the president said.

Robert Redfield, director of the Centers for Disease Control and Prevention, said, “The risk is low. We need to get on with our normal lives.”

In response to a reporter’s question, Mr. Trump said the U.S. is also considering restrictions at the Mexican border. On Sunday, Mr. Trump said on Twitter that travelers from high-risk countries or areas wouldn’t only be screened for the virus prior to boarding but also when they arrive in the U.S.