In picking Austin, who would be the first black US secretary of defence, Biden bypassed Michelle Flournoy, who would have been the first woman defence secretary and had been seen as the leading contender for the job.

Austin, who headed US Central Command under Obama, will need a waiver from Congress since it has been less than seven years since he served.

His nomination could draw fire from some progressive groups given his role on the board of a number of companies, including weapons maker Raytheon Technologies Corp.

Biden, who takes office on Jan 20, also announced members of his health team to lead the administration’s response to the raging Covid-19 pandemic.

Biden chose California Attorney-General Xavier Becerra for secretary of health and human services and picked Dr Rochelle Walensky, chief of infectious diseases at Massachusetts General Hospital in Boston, to run the US Centers for Disease Control and Prevention.

Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, was named as Biden’s chief medical adviser on the virus.

Biden’s first major challenge in the White House will be containing a resurgent Covid-19 virus that has killed more than 282,000 Americans, and finding ways to jump-start an economy still reeling from millions of pandemic-fuelled job losses.

He installed Jeff Zients, an economic adviser known for his managerial skills, as Covid-19 “czar” to oversee a response that will include an unprecedented operation to distribute hundreds of millions of doses of a new vaccine, coordinating efforts across multiple federal agencies.

“This team of world-class medical experts and public servants will be ready on Day One to mobilise every resource of the federal government to expand testing and masking,” Biden said in a statement, adding they would “oversee the safe, equitable, and free distribution of treatments and vaccines”.