WASHINGTON, (Reuters) –Dr. Anthony Fauci, a top U.S. official in infectious diseases said Friday that a ban was possible on flights to southern Africa and that the United States was rushing data collection on the COVID-19 variant.

He said that no decision had been taken to stop flights.

The new mutation, which was detected in South Africa by the authorities, has sparked alarm around the world. Britain and the European Union have tightened border control as scientists attempt to determine if it is vaccine resistant.

However, the World Health Organization (WHO) cautioned against overreaching measures. South Africa stated that a ban by Britain on flights was too rushed.

Fauci told CNN that “there is always the option of doing what the UK did, namely blocking travel from South Africa or related countries,” in an interview.

It’s something to think about, and be prepared for. It’s clear that you are ready to defend the American people. However, you must ensure that there’s an adequate basis to do so,” he stated.

“Obviously we’ll take a decision as soon we can as we get more information.”

Fauci indicated that U.S. scientists were meeting with South African counterparts to discuss the variant B.1.1.529. The new variant has raised concerns about transmissibility, and whether it may evade immune responses.

He said that no evidence was available that the variant had been introduced in America.