After being brutally criticised for his suggestion that people could try injecting disinfectant to fight the novel Coronavirus, US President sought to play down his statement, claiming he was being “sarcastic.”

“I was asking a question sarcastically to reporters like you, just to see what would happen,” he told journalists at the White House.

President Donald Trump late Thursday turned during a press conference to government scientists in the room and asked them about disinfectant.

“I see the disinfectant that knocks it out in a minute, one minute. And is there a way we can do something like that by injection inside or almost a cleaning? As you see, it gets in the lungs, it does a tremendous number on the lungs, so it would be interesting to check that… It sounds interesting to me,” Trump said, without explaining the type of disinfectant he was talking about.

After a scientist made a presentation at the daily Coronavirus Task Force briefing on Thursday showing that COVID-19 virus is killed by sunlight in two minutes, Trump suggested bringing powerful light inside the body.

William Bryan, science and technology advisor to the Department of Homeland Security secretary, told reporters at the White House that government scientists had found ultraviolet rays had a potent impact on the pathogen, offering hope that its spread may ease over the summer.

“Our most striking observation to date is the powerful effect that solar light appears to have on killing the virus, both surfaces and in the air,” he said.

“We’ve seen a similar effect with both temperature and humidity as well, where increasing the temperature and humidity or both is generally less favorable to the virus.”

After Bryan was done speaking, President Donald Trump said he wondered whether the body could be cleansed with a “very powerful light”.

“So supposing we hit the body with a tremendous – whether it’s ultraviolet or just a very powerful light – and I think you said that hasn’t been checked because of the testing,” President Trump said.

“And then I said, supposing you brought the light inside the body, which you can do either through the skin or some other way, and I think you said you’re going to test that, too, sounds interesting,” he said. The White House coronavirus task force coordinator Dr Deborah Birx was also in attendance. People tweeted videos of her surprised expression when President Trump was speaking.

He then went on to talk about the “disinfectant to cleanse body”.