Day after another White House staff member was diagnosed with coronavirus, United States Vice President Mike Pence's press secretary, the wife of one of President Donald Trump's senior advisers, has tested positive for Covid-19, raising alarm about the virus' potential spread within the White House's innermost circle.

Mike Pence
Pence spokeswoman diagnosed with coronavirus.

The diagnosis of Katie Miller, who is married to White House immigration adviser and speechwriter Stephen Miller, was revealed by the US President in a meeting with Republican lawmakers yesterday, a day after news that Trump's personal valet had tested positive for the deadly virus.

"Katie, she tested very good for a long period of time and then all of a sudden today she tested positive," Trump said, noting he himself had not been in contact with her but that she had spent time with the vice president. "I understand Mike has been tested...and he tested negative."

The White House has begun daily testing for Mike Pence and Donald Trump, and has claimed to be taking "every single precaution to protect the US president".

US death toll stands at 76,000

The US death toll is now more than 76,000 and states are beginning to reopen.

Around six members of Mike Pence's team were abruptly taken off his plane, Air Force 2, after it was held on the tarmac outside Washington, DC for over an hour on Friday, as he prepared to travel to Iowa to meet religious leaders.

The staff members had had recent contact with Miller, according to a US official cited in the media pool report. The president and vice-president had not.

The president has made it clear that he does not like the way that a mask looks on him.

He said last month that he believes wearing a mask would not make a good impression on world leaders and others he meets.

"As I greet presidents, prime ministers, dictators, kings, queens ... I don't see it for myself, I just don't," Trump told a journalist.

For some, the president's refusal to wear a mask is more than a question of style. It is a political statement.

'Health crisis is under control'

Trump and the other officials at the White House want to give people the impression that the health crisis is under control and that soon the economy will be on back on track.

The decision of the president and others at the White House not to wear masks, writes the Washington Post's David Nakamura, conveys "a sense of confidence that life, at least for the nation's most prominent resident, is returning to a semblance of normalcy during the coronavirus pandemic - a visual cue to the public that conditions are improving as Trump pushes to restart sectors of the economy".

When asked about the possibility of an outbreak in the White House, Trump told reporters: "All you can do is take precautions and do the best you can."

He also said he was correct not to wear a mask while visiting the World War II memorial in Washington for VE Day, because the elderly veterans there with him were "far away".

"Plus the wind was blowing so hard and such a direction that if the plague ever reached them, I'd be very surprised," he added.

Earlier on Friday, White House Press Secretary Kayleigh McEnany defended the measures taken by the White House to keep officials safe.

"We've taken every single precaution to protect the president," McEnany said.

Trump's Chief of Staff Mark Meadows also told reporters: "This is the safest place you can come to."

(With agency inputs)