President Donald Trump's White House has launched a Covid-19 website in which it blamed the origins of the coronavirus on a lab leak in China while criticising Democratic former President Joe Biden, former top US health official Anthony Fauci and the World Health Organization.

The website launched on Friday was also critical of steps like social distancing, mask mandates and lockdowns. The Covid.gov website, previously focused on promoting vaccine and testing information, now includes a full-length image of Trump and criticises the pandemic policies implemented under Biden.

Trump began a 12-month process of withdrawing the U.S. - by far the WHO's largest financial backer - from the agency when he took office in January.

Fauci, Biden and WHO had no immediate comment.

Soon after taking office, Trump also said that Fauci, who has faced threats since leading the country's Covid-19 response, should hire his own security and ended US security for him.

A CIA spokesperson said in January that the CIA has assessed that the Covid-19 pandemic is more likely to have emerged from a lab than from nature. The CIA had said it had "low confidence" in its assessment and that both scenarios — lab origin and natural origin — remain plausible.

China's government says it supports and has taken part in research to determine Covid-19's origin, and has accused Washington of politicising the matter, especially because of efforts by US intelligence agencies to investigate.

Beijing has said there was no credibility to claims that a laboratory leak likely caused the pandemic.

'Covid-19 misinformation'

Under a section titled "Covid-19 misinformation," the site also accused public health officials under the previous administration of demonising "alternative treatments" and colluding with social media companies to censor dissenting views about the pandemic — a charge frequently echoed by US conservatives.

The Biden administration has previously rejected the charge that it was suppressing or censoring conservative perspectives.

The website revamp comes after layoffs began earlier this month at major US health agencies, as the Trump administration embarks on a sweeping and scientifically contested restructuring that will cut 10,000 jobs.

Health secretary Robert F. Kennedy Jr — who has alarmed health experts with his rhetoric downplaying the importance of vaccines — said the layoffs were part of a major reform of his department, aiming to refocus efforts on chronic disease prevention.

More than one million people died of Covid-19 and related illnesses in the United States, and millions more were lost around the world.