Former Vice President Joe Biden took direct aim at President Trump on Tuesday, saying that Trump, who once called himself a "wartime president" taking on the coronavirus pandemic, seems to have now "surrendered."

"Remember when he exhorted the nation to sacrifice together in the face of this ... 'invisible enemy'? What happened? Now it's almost July, and it seems like our wartime president has surrendered," Biden said in prepared remarks.

The presumptive Democratic presidential nominee urged Trump to "immediately" adopt his updated plan for dealing with the COVID-19 crisis in the United States.

"American people [didn't] make enormous sacrifices over the past four months so they could just waste their time," Biden said. "They didn't make these sacrifices so you could ignore the science and turn responsible steps like wearing masks into a political statement. And they certainly didn't do it, Mr. President, so you could wash your hands and walk away from this responsibility."

Speaking at Alexis duPont High School in his hometown of Wilmington, Del., the former vice president went through his new COVID-19 response, which piggybacks off of his original plan released in March.

Among its provisions, Biden's plan calls for scaling up testing and hiring at least 100,000 Americans to build a national workforce of contact tracers. He's also seeking to accelerate vaccine plans and implement a coordinated effort to build up supplies.

Biden took issue with the White House's reopening recommendations, saying that while the Centers for Disease Control and Prevention attempted to push through "guidelines about what the stages of reopening should look like, the administration delayed and scaled back those plans."

"We need clear, evidence-based steps that states can adopt now — both the standards that must be met in order to safely proceed with further openings, and the reimposition of social distancing rules when cases begin to rise," Biden added.

The former vice president's address comes as the country has recorded nearly 2.7 million positive cases of COVID-19 and nearly 130,000 deaths.

In recent days, sharp increases in cases have been seen in several states that originally reported lower totals this spring and had begun to reopen — including Florida, Texas, Arizona and Georgia, according to NPR's case tracker.

On Capitol Hill Tuesday, Dr. Anthony Fauci, the country's top infectious disease expert, warned members of Congress that he "would not be surprised if we go up to 100,000 [confirmed COVID cases] a day if this does not turn around."

Before Biden's speech, the campaign released a statement saying that "minutes after [Biden] is declared the winner of the election" he will ask Fauci to serve in his administration and continue working to combat the virus.

Trump's reelection campaign briefed reporters prior to Biden's remarks. Tim Murtaugh, the campaign's director of communications, said that Biden has attempted to use the coronavirus as a campaign issue and tried to undermine confidence in the federal response to the virus in order to bolster his political aspirations.

Following his speech, Biden took questions from the press — something that the Trump campaign has criticized him for avoiding in recent weeks.

Biden was asked repeatedly about the allegation that Russia placed bounties on U.S. troops stationed in Afghanistan and that Trump was made aware of the situation in the spring of 2019.

"If these allegations are true, and he did nothing about any of this, then in fact I think the public should — unrelated to my running — conclude that this man isn't fit to be president," Biden responded. He added later that he may ask for a classified briefing on the subject.

Contrasting with the Trump campaign, Biden said he doesn't plan to hold campaign rallies but will continue traveling to states to campaign. He also disclosed that he has not been tested for COVID-19 yet.

Looking ahead to the rest of the summer and into the fall, Biden was asked about his preparation for upcoming debates against Trump.

"I can hardly wait," Biden responded.

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