The United States is poised to announce a ban on travel Sunday from coronavirus-hit Brazil, a top aide to US President Donald Trump said.

"I think that we'll have a new travel decision today with respect to Brazil and just like we did with the UK and Europe and China, and we hope that'll be temporary," Robert O'Brien, the US national security advisor, said on CBS's "Face the Nation."

"But because of the situation of Brazil, we're going to take every step necessary protecting American people," he said.

The United States had previously cut off travel from China, Europe and Britain as the virus surged in those countries.

Brazil has emerged as the latest COVID-19 flashpoint, second only to the United States in the number of cases and with a death toll that has surpassed 22,000.