By Nandita Bose and David Shepardson

NANTUCKET, MA/WASHINGTON (Reuters) -The United States will bar entry to most travelers from eight southern African countries beginning next week over concerns about a new coronavirus variant found in South Africa, President Joe Biden said on Friday.

The restrictions, which go into effect Monday, do not ban flights or apply to U.S. citizens and lawful U.S. permanent residents, a Biden administration official said.

The U.S. is among countries around the world that rushed to suspend travel from southern Africa on news over the new variant, named omicron, which the World Health Organization said was "of concern."

The restrictions apply to South Africa, Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique, and Malawi. Most non-U.S. citizens who have been in those countries within the prior 14 days will not be allowed into the United States.

"As a precautionary measure until we have more information, I am ordering additional air travel restrictions from South Africa and seven other countries," Biden said in a statement. "These new restrictions will take effect on November 29. As we move forward, we will continue to be guided by what the science and my medical team advises."

Another administration official warned that the United States could add countries to the restriction list if the variant spreads.

Delta Air Lines and United Airlines both fly to South Africa and United is set to resume nonstop flights from Newark to Cape Town on December 1. Shares of both airlines closed down more than eight percent on Friday.

Biden on Friday called on nations meeting at the World Trade Organization next week to agree to waive intellectual property protections for COVID-19 vaccines in the wake of the discovery of the new variant.

"The news about this new variant should make clearer than ever why this pandemic will not end until we have global vaccinations," Biden said in a statement.

Some public health experts have said the United States has not done enough to provide vaccines overseas, particularly as it pushed forward with booster shots for its own citizens.

Earlier, top U.S. infectious disease official Dr. Anthony Fauci said the United States was rushing to gather data on the new COVID-19 variant.

It could take weeks for scientists to fully understand the variant's mutations. Health authorities are seeking to determine if omicron is more transmissible or infectious than other variants and if vaccines are effective against it.

The United States only lifted travel restrictions on South Africa on November 8.

One administration official said the restrictions are expected to take effect at 12:01 a.m. EST Monday and came after a high-level administration meeting Friday afternoon to discuss the issue.

The Biden administration was holding a briefing with U.S. airlines to discuss the restrictions on Friday.

In January, Biden imposed a ban on most non-U.S. citizens entering the country who had recently been in South Africa.

The United States only lifted the travel curbs on 33 countries including South Africa, China, much of Europe, India, Brazil, Ireland, Britain and Iran on November 8 after blocking the entry of most foreign nationals who had recently been in those countries since beginning in early 2020.

(Reporting by David Shepardson and Nandita Bose; Editing by Leslie Adler)