Bob Woodward speaks at the Newseum during an event marking the 40th anniversary of Watergate at the Newseum in Washington, DC. File / AFP

President Donald Trump seemed to understand the severity of the coronavirus threat even as he was telling the nation that the virus was no worse than the seasonal flu and insisting that the US government had it totally under control, according to a new book by journalist Bob Woodward.

"You just breathe the air and that’s how it’s passed,” Trump said in a Feb.7 call with Woodward. "And so that’s a very tricky one. That’s a very delicate one. It’s also more deadly than even your strenuous flu.”

"This is deadly stuff,” the president repeated for emphasis.

Trump told Woodward on March 19 that he deliberately minimised the danger. "I wanted to always play it down,” the president said.

The Washington Post, where Woodward serves as associate editor, reported excerpts from the book, "Rage" on Wednesday, as did CNN. The book also covers race relations, diplomacy with North Korea and a range of other issues that have arisen during the past two years.

The book is based in part on 18 interviews that Woodward conducted with Trump between December and July.

The book is an unwelcome return to focus on Trump’s handling of the pandemic just as he is trying to project the virus as under control and eager to see a return to normal activity leading up to the Nov. 3 presidential election.

Democratic presidential nominee Joe Biden seized on the book's allegations that Trump played down the threat of the virus to the public but knew the dangers it posed. Biden called Trump's handling of the pandemic "beyond despicable."

"It’s a dereliction of duty. It’s a disgrace,” Biden said.

"Trump never did seem willing to fully mobilise the federal government and continually seemed to push problems off on the states,” Woodward writes. "There was no real management theory of the case or how to organise a massive enterprise to deal with one of the most complex emergencies the United States had ever faced.”

White House press secretary Kayleigh McEnany said the president's words to the public were designed to express confidence and calm at a time of insurmountable challenges.

"The president has never lied to the American public on COVID. The president was expressing calm and his actions reflect that," McEnany said.

McEnany took questions about the book during a briefing at the White House on Wednesday. She said his actions reflect that he took COVID-19 seriously. She noted that the president put in place travel restrictions with China on Jan. 31 and that some Democrats had criticised the move.

House Speaker Nancy Pelosi, D-Calif., said the president's comments to Woodward connoted weakness and a disdain for science.

"What he was actually saying is, ‘I don't want anybody to think anything like this happened on my watch so I'm not going to call any more attention to it," Pelosi said during an interview on MSNBC.

Woodward's book is his second on the Trump White House. The first, published in 2018, portrayed Trump in an unflattering light, and the president fumed at staff that he was not interviewed for it, according to two former White House officials and Republicans close to the White House. They were not authorised to speak publicly about private conversations and discussed the matter on condition of anonymity.

Trump was convinced that had he talked to Woodward, he could have led to a more favourable depiction in the book, according to the officials. Trump had always held Woodward in high regard – he considered the journalist as the biggest star in the field – and told aides that he insisted on being interviewed if Woodward were to write again, the officials said.

Associated Press