A Republican-led US Senate committee on Thursday voted to hold the country's former top infectious diseases official Anthony Fauci in contempt of Congress, in an escalation of efforts to blame him for potential Covid-19 pandemic missteps.

On the advice of his lawyers, Fauci last week had invoked his constitutional right to stay silent to prevent self-incrimination under antagonistic questioning from Republican senators, as they probed him over unsubstantiated claims that the origins of the pandemic were covered up.