The top US infectious disease official, Dr. Anthony Fauci, told President Joe Biden on Sunday it will take about two weeks to have definitive information on the new coronavirus variant Omicron that has sparked new travel restrictions and shaken financial markets, according to Reuters.

Fauci said he believes existing vaccines are likely to provide “a degree of protection against severe cases of Covid”, and officials reiterated their recommendation for vaccinated Americans to get booster shots, according to a readout of the briefing.

Biden is due to update the public on the new variant and the US response today, the White House said.