President Donald Trump, confined to the White House where he is being treated for Covid-19, said on Thursday he does not believe he is contagious and is feeling good enough to resume campaign rallies as he tries to boost his flagging re-election bid.

“I’m back because I’m a perfect physical specimen,” Trump told Fox Business Network’s Maria Bartiromo in his first interview since it was revealed nearly a week ago that he had tested positive for the coronavirus.

Trump’s contention he was no longer contagious was not yet backed up by solid evidence from his doctors. The White House has refused to say when his last negative test for the virus was and, as a result, it is unclear how long he has been positive.

The President is under pressure to actively campaign again to try to inject new energy into his re-election bid as he faces a deficit in opinion polls in battleground states.

“I’m feeling good, really good,” said Trump, who spent three nights being treated at a military hospital outside Washington until his discharge on Monday. Trump said he had stopped taking “most therapeutics” for the virus but was still on steroids.

With layoffs increasing doubts about the fragile economic recovery, Trump said he called off talks with Congress for a fresh stimulus for the economy because they were not going anywhere.