Joe Biden will wear a mask if he goes out in public, the former vice-president and probable Democratic presidential nominee said on Sunday.

Donald Trump said on Friday he would not wear a mask, despite new guidelines issued by the White House that day – and announced from the Briefing Room podium by the president – for people to wear face coverings in public places.

In an interview with ABC’s This Week, Biden also defended his work as vice-president in the Obama administration in terms of preparing for such a pandemic.

Trump has repeatedly sought to blame his predecessor for the federal government’s slow and disjointed response to the arrival on US soil of Covid-19, the virus which by Sunday had infected more than 312,000 Americans and killed nearly 8,500.

At the White House on Friday, Trump told reporters “the [Centers for Disease Control and Prevention] is advising the use of non-medical cloth face covering as an additional voluntary public health measure”.

But he added: “This is voluntary. I don’t think I’m going to be doing it.”

In an interview on ABC’s This Week on Sunday, Biden, 77, sequestered at home in Wilmington, Delaware, was asked if he would wear a mask.

“Yes,” he said. “Look, I think it’s important to follow the science, listen to the experts do what they tell you.”

Trump, 73, said “I just don’t want to wear one myself” and added that he was “feeling good”.

The wearing of masks is recommended as a way to stop people who have the virus but may not be showing symptoms from infecting others.

Trump ploughed on: “Somehow, sitting in the Oval Office behind that beautiful Resolute Desk, the great Resolute Desk, I think wearing a face mask as I greet presidents, prime ministers, dictators, kings, queens, I don’t know, somehow I don’t see it for myself. Maybe I’ll change my mind, but this will pass, and hopefully it will pass very quickly.”

Biden responded: “[Trump] may not like how he looks in a mask but the truth of the matter is … follow the science. That’s what they’re telling us. So if I go out in public, and I have not gone to commercial places of late, I haven’t gone to my local church … but my generic point is that you should follow the science.”

Biden also described preparations the Obama administration took to handle any pandemic, moves he said Trump had dismantled.

“We did a lot to prepare,” he said. “As you know … we set up a pandemic office within the White House, we expanded CDC in other countries so we could in fact, observe, see when things were coming, how things were moving.

“We put people in China. I mean we did a whole lot of things, and they got a very detailed breakdown on this by a briefing, the Trump administration, when we transitioned out of office, but the president dismantled almost all of that and he drastically cut the budget for the CDC … so he didn’t follow through on any of what we suggested was going to be a real problem.

“We can do much better than [what is] being done now.”

Appearing on NBC’s Meet the Press, Jay Inslee, governor of Washington state where the virus first took hold on US soil, slammed Trump over the White House response.

“This is ludicrous that we do not have a national effort in this,” Inslee said. “To say [the federal government is] a backup” – as Trump has repeatedly said this week “…Can you imagine if Franklin Roosevelt said: ‘I’ll be right behind you Connecticut, good luck building those battleships’?

“If he wants to be a wartime president, be a wartime president. Show some leadership. Mobilize the industrial base of the United States, that’s what we need.”

On ABC, Biden also weighed in on the controversial dismissal of the US navy captain Brett Crozier, calling it “close to criminal”.

Capt Crozier was removed from command of the USS Theodore Roosevelt this week after he wrote a memo about concerns for his crew on the aircraft carrier with coronavirus cases aboard. Capt Crozier was cheered from the ship but on Saturday Trump criticized him for writing the letter.

“I thought it was terrible what he did, to write a letter,” Trump said. “This isn’t a class on literature. This is a captain of a massive ship that’s nuclear-powered.”

The defense secretary, Mark Esper, told CNN’s State of the Union on Sunday “there is an investigation ongoing” but repeated that he supported the decision to fire Crozier because Thomas Modly, the acting navy secretary, had lost confidence in him.

“When all those facts come to bear we’ll have a chance to understand” why the decision was taken, Esper said.

Esper also dismissed reports that, as the Washington Post put it, Modly “told one colleague [on] Wednesday, the day before he announced the move: ‘Breaking news: Trump wants him fired’.”

Biden said it was “close to criminal the way they’re dealing with this guy. The idea that this man stood up and said what had to be said, got it out that his troops, his navy personnel were in danger … Look how many have the virus.

“I think he should have a commendation rather than be fired.”

Esper also appeared on ABC, where he said US military personnel would soon be required to wear masks on duty.