NEW DELHI – President Donald Trump and White House officials downplayed coronavirus concerns Tuesday, describing the epidemic as "very well under control in our country" despite a sharp increase in cases globally and warnings of "severe" disruptions.

But lawmakers expressed growing unease about the virus and questioned whether the administration was doing enough to address the risks.

Speaking to reporters in India, where he was taking part in a state visit, Trump noted that few people have been diagnosed with the virus in the U.S. and claimed that the "whole situation will start working out." But markets tumbled hours later as health officials warned of a more extensive impact in the United States.

"Disruption to everyday life may be severe," said Nancy Messonnier, director of the Centers for Disease Control and Prevention's National Center for Immunization and Respiratory Diseases. Schools could be closed, public gatherings suspended and employees forced to work remotely, she said.

The new coronavirus presents a major test for the Trump administration in terms of managing public expectations and responding to the illness while coping with the potential economic and political fallout. A day after the White House requested $2.5 billion in emergency funding for the virus from Congress – including $1.25 billion in new money – there were signs of unease on Capitol Hill.

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Democrats immediately slammed the request as insufficient. Some Republicans also appeared to be leaning into the White House to step up its game.

Missouri Sen. Roy Blunt, chairman of the Republican Policy Committee, said that more than $200 million is available to meet the "immediate need" posed by the virus. Blunt said the Senate is working with the White House to determine whether the $2.5 billion proposed spending plan is adequate.

Asked whether the administration is sending mixed messages with the president's rosy predictions, Blunt indicated that it was.

"I don’t know what the White House is saying,” Blunt said. "People who work for the White House are not saying that."

Blunt's remarks followed a hearing in which Sen. John Kennedy, R-La., laid into acting Homeland Security Secretary Chad Wolf, asserting that the administration had not provided critical information about the virus to the public.

"How many cases are there? How many cases, based on modeling, do they think we’ll have?" Kennedy said after the hearing. “How is the virus transmitted? What is the mortality rate? How many masks are we going to need? Are we working on getting more? How many respirators are we going to need? Are we working on getting more? They need to talk straight up to the American people.”

China reported 409 new cases of the virus Tuesday, raising the mainland’s total to 77,150. The 150 new deaths from the illness raised China’s total to 2,592. Elsewhere, a surge in reports of new cases hit Iran, Italy and South Korea.

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There are 57 confirmed cases of coronavirus in the United States, according to the World Health Organization, but the Centers for Disease Control and Prevention said the risk for transmission remains "low."

Speaking in India on Tuesday, Trump insisted that the virus was under control.

"But the people are getting better. They're all getting better," Trump said. "I think that whole situation will start working out. A lot of talent, a lot of brainpower is being put behind it."

Trump defended the decision to repatriate and quarantine some of those affected when asked by reporters Tuesday about his 2014 tweets criticizing President Barack Obama's response to the Ebola crisis, including allowing a patient to return to the U.S.

"There is a big difference in case you don’t know between Ebola and coronavirus. Big, big difference. It’s like day and night,” Trump said.

Trump said "we're very close to a vaccine," though senators briefed on the virus by administration officials Tuesday appeared to differ.

Coming out of the closed-door briefing, Blunt told reporters, “we will not have a vaccine in the next 12 or 18 months,” noting the difficulty in producing and approving a vaccine in a short period of time. Some of the emergency funding requested by the White House late Monday would be used for vaccination development.

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The president also pushed back on criticism from Democrats, including Senate Minority Leader Chuck Schumer, D-N.Y., who said Trump was not taking the outbreak seriously enough and that he wants to redirect money from other health programs, including the Ebola response.

"I see that Chuck Schumer criticized that he thought it should be more. And if I gave more, he would say it should be less," Trump told reporters on Tuesday.

Trump's comments came as he finished up a 36-hour whirlwind visit to India, which spanned three cities and included a welcome rally of more than 100,000 people in Prime Minister Narednra Modi's home state of Gujarat.

Contributing: Kevin Johnson, Nicholas Wu