Treasury Secretary Steven Mnuchin warned unemployment could hit 20% without action: Sources

President Donald Trump on Tuesday predicted "we're going to win" what he called a "war" against the coronavirus as he briefed the nation one day after recommending new, stricter nationwide guidelines that prompted much of America to shut down in an effort to slow the spread of the disease.

"If we do this right our country -- and the world frankly -- but our country but can be rolling again pretty quickly, pretty quickly. We have to fight that invisible enemy that I guess is unknown but we’re getting to know it a lot better, he said.

"At my direction, [Treasury] Secretary Mnuchin is meeting today with senators on additional stimulus packages," Trump said, adding that the administration is looking at a range of relief from help for the airline industry to loans for small businesses to financial flexibility for fast food workers.

In the most dramatic move to help average American workers, Mnuchin announced that the administration is looking at sending checks directly to households that are hurting – possibly within the next two weeks, supporting an idea that began in Congress.

"We are looking at sending checks to Americans immediately. What we heard from hardworking Americans, many companies are now shut down whether bars or restaurants, Americans need cash now and the president wants to get [them] cash now. I mean now in the next two weeks," Mnuchin said. "We want to make sure Americans get money in their pockets quickly," he said, adding that more details would be revealed later today.

"I think we'll do something to get money to them as quickly as possible," Trump said.

Asked for a timeline for how quickly this could come together, Mnuchin said, "The president has instructed me, we have to do this now. This is now."

"We're going big," Trump added.

Americans can expect the first checks of "at least $1,000" to go out by the end of April, if Congress approves the proposal the White House pitched to Senate Republicans, a senior administration official told ABC News Tuesday evening. The official said the size of the check would depend "on where we set the income cap for eligibility."

A second check would go out two months later -- if the national emergency continued.

Tune into ABC News Live at 1 p.m. EDT every weekday for the latest news, context and analysis on the novel coronavirus, with the full ABC News team where we will try to answer your questions about the virus.

Here are Tuesday’s most significant developments in Washington:

Here is how developments unfolded on Tuesday.

Treasury Secretary says coronavirus could bring unemployment rate to 20% without action

During a meeting with Republican senators on Tuesday, Treasury Secretary Steven Mnuchin said the virus could raise the U.S. jobless rate to 20% if the government did not intervene, ABC News has confirmed.

A senior administration official and one senior aide for a GOP senator told ABC News that Mnuchin made the comments while laying out a potential scenario without government intervention.

A Treasury Department spokesperson said it would be accurate to say that Mnuchin used the mathematical examples to demonstrate the potential risk. But because the administration, Fed and others are doing the right things, that risk would not materialize.

Senate GOP and White House discussing $1 trillion economic stimulus

Following the White House briefing, Secretary Mnuchin met behind closed doors with Senate Republicans for a little over an hour Tuesday -- with some of the focus on what a third massive stimulus package will look like.

Several senators told ABC News they’re discussing $1 trillion as the top-line number -- and not $850 billion as mentioned at the White House briefing.

South Dakota Sen. Mike Rounds, a fiscal conservative, said, "It may go over one trillion.

Majority Leader Mitch McConnell, R-Ky., made it clear the Senate won’t adjourn until further economic stimulus measures are passed, despite increasing lawmaker concerns that being in session could risk spreading the virus.

"It is my intention that the Senate will not adjourn until we have passed significant and bold new steps above and beyond what the House has passed," McConnell said in a Senate floor speech Tuesday morning.

The leader said he is looking to address three major priorities: Providing more direct assistance for American workers and families, providing more aid to small businesses and continuing providing support to medical professionals.

Meanwhile, a revised version of the House Democrats' "Families First Coronavirus Response Act" awaits a Senate vote with the goal of providing workers paid sick leave and other immediate economic relief amid the outbreak.

New report that makes deadly prediction has sober impact on White House response

Ambassador Deborah Birx, the White House point person on the coronavirus, confirmed Tuesday that an Imperial College London report that warns, without strong action to slow the spread, up to 2.2 million Americans could die from the coronavirus, was a driving force behind the new stepped-up but still just recommended, not mandatory, restrictions.

President Trump denied his approach toward dealing with the virus crisis had turned sober when asked whether the report had prompted what appeared to be a marked changed in tone this week.

What to know about Coronavirus:

Mnuchin says rattled Wall Street markets will stay open

Mncuhin also made clear that there's every intention to keep the Wall street markets open, though he floated the possibility of shortening market operating hours if that is deemed necessary at some point.

"We absolutely believe in keeping the markets open, okay, Americans need to know they have access to their money," Mnuchin said. "Everybody wants to keep it open. We may get to a point where we shorten the hours if that’s something they need to do. But Americans should know that we are going to do everything to make sure that they have access to money to their banks, to the money to their 401-k, and to the money in stocks," he said.

Trump spun the growing economic crisis in a positive light. "I don't think in terms of recession. I think in terms of getting it out. When we are finished with the virus, we'll win. We will win. When that victory takes place, our economy is going to go through the roof. It is so built up. It is ready to go in an upward direction. There is a really tough enemy but we have to knock it out," Trump said. "I actually think we’ll have an economy like we’ve never had before."

Fauci pleads: '"We can't do this without the young people cooperating, please cooperate with us'

National institute of Allergy and Infectious Diseases Director Anthony Fauci pleaded with young people to cooperate with the government's urgent guidance that they take part in social distancing-- a key part of the 15-day guidelines Trump and the White House issued Monday.

"We can't do this without the young people cooperating, please cooperate with us," Fauci said. He hearkened back to his own youth, saying "I felt I was invulnerable" but warned that that sort of attitude -- while it may not put them personally at risk, could put their loved ones at risk.

"When we're asking the young people to help us with this mitigation strategy by staying out of the bars, staying out of the restaurants, really trying to distance yourself. Don't get the attitude well I'm young, I'm invulnerable … what you might inadvertently do, and I don’t you want to do that, you don't want to put your loved ones at risk. Particularly the ones who are elderly and the ones who have compromised conditions," he said.

Fauci said it would be "several weeks and maybe longer" before it could be known whether the new White House guidelines and other measures were working to slow the spread of the virus.

Trump defends calling it a 'Chinese virus'

--Trump defended his use of the term "Chinese virus" as "very accurate" in Tuesday's press conference, saying he started using that phrase in reaction to China spreading disinformation that the U.S. military was behind the virus.

"I did not appreciate the fact that China was saying our military gave it to them. Our military did not give it to anybody," Trump said.

Trump says political attacks self-defense

Questioned by ABC News Chief White House Correspondent Jon Karl about his continued attacks on Democrats, in spite of his call in his national address last week to put politics aside, Trump defended his attacks as self-defense. "When they attack me ... I’m not going to let them get away with it, I can't do that," he said.

Asked by Karl what actions the administration is taking to ensure elections are able to be protected amid the coronavirus outbreak, Trump said it's very simple: "we’re getting rid of the virus."

"What I am doing, Jon, is very simple, we’re getting rid of the virus," Trump said. That's the only thing we can do. For the markets, for everything, it’s very simple, simple solution, we want to get rid of it," Trump said. "The best thing we can do is get rid of the virus. Once that’s gone it’s going to pop back like nobody has ever seen before that's my opinion. I think it will pop back like nobody has seen before."

Trump says FDA allowing states to approve tests

Trump began the news conference by saying the FDA has made a regulatory change to give states the ability to approve tests developed in laboratories in the states.

"All states can now authorize tests developed and used within their borders in addition to the FDA," Trump said. "The states are very much involved -- they have been involved from the beginning -- but we’re stepping it up as much as we can, and the testing procedures are going well."

"Today we’re also announcing a dramatic expansion of our Medicare tele-health services," saying they will not enforce penalties on doctors either. "Medicare patients can now visit any doctor by phone or video conference at no additional cost, including with commonly-used services like Facetime and Skype."

Pentagon to provide respirators and ventilators

Defense Secretary Mark Esper announced that the Pentagon will provide civilian health authorities with 5 million respirator masks and 2,000 specialized ventilators in response to the pandemic.

Esper told reporters in an afternoon briefing that the ventilators are designed for use by deployed troops and the military will need to train civilians on how to use them. He added that the first million respirator masks will be made available immediately.

ABC News' Jordyn Phelps, Ben Gittleson and Elizabeth McLaughlin contributed to this report.