The former head of the US Centers for Disease Control and Prevention has said he was “sidelined” over his views on the origins of the Covid-19 pandemic.

Dr Robert Redfield was the key witness in a US congressional committee’s first public hearing as it investigates how the coronavirus emerged.

He said he was cut out of early discussions on where the virus came from because he suspected a lab leak.

The accusation was dismissed by Dr Anthony Fauci as “completely untrue”.