A feverish US President Donald Trump has been flown to hospital after testing positive for coronavirus.

The White House said the president was "fatigued but in good spirits" and was taken to hospital as a precaution.

Mr Trump received an experimental drug cocktail injection at the White House after he and First Lady Melania Trump both tested positive for Covid-19.

It is a potential setback as he trails Democratic challenger Joe Biden a month before the presidential election.

Wearing a mask and suit, Mr Trump walked out across the White House lawn on Friday afternoon to his helicopter, Marine One, for the short flight to Walter Reed National Military Medical Center in the Washington DC suburbs.

He waved and gave a thumbs-up to reporters but said nothing before boarding the aircraft.

In a video posted to Twitter, Mr Trump said: "I think I'm doing very well. But we're going to make sure that things work out. The first lady is doing very well. So thank you very much."

The president's children, Ivanka and Eric, retweeted his post, praising him as a "warrior". Ms Trump added: "I love you dad."

Mr Trump was admitted to the presidential suite at Walter Reed, which is where US presidents usually have their annual check-up.

Shortly before midnight, he tweeted again: "Going welI, I think! Thank you to all. LOVE!!!"

White House press secretary Kayleigh McEnany said in a statement: "President Trump remains in good spirits, has mild symptoms, and has been working throughout the day.

"Out of an abundance of caution, and at the recommendation of his physician and medical experts, the president will be working from the presidential offices at Walter Reed for the next few days.

"President Trump appreciates the outpouring of support for both he and the first lady."

Mr Trump's symptoms include a low-grade fever, according to the BBC's US partner CBS News.

White House communications director Alyssa Farah said the president had not transferred his powers to Vice-President Mike Pence.

"The president is in charge," she said.

But he pulled out of a video conference call with vulnerable seniors scheduled for Friday, leaving Mr Pence to chair the meeting.

Under the US constitution, if Mr Trump did become too ill to carry out his duties, he could hand over his powers to the vice-president temporarily.

That means Mr Pence - who tested negative for Covid-19 on Friday - would become acting president until Mr Trump was fit again and could resume work. (BBC)

•PHOTO: White House Chief of Staff Mark Meadows (R) watches as US President Donald Trump walks off Marine One while arriving at Walter Reed Medical Center in Bethesda, Maryland on October 2, 2020. Brendan Smialowski / AFP

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