WASHINGTON- U.S. land borders with Canada and Mexico will remain closed to non-essential travel until at least Aug. 21, the U.S. Homeland Security Department said on Wednesday.

The 30-day extension came after Canada announced Monday it will start allowing fully-vaccinated U.S. visitors into the country on Aug. 9 for non-essential travel after the COVID-19 pandemic forced an unprecedented 16-month ban that many businesses complained was crippling them. urn:newsml:reuters.com:*:nL1N2OV1MH

One difficult question for the Biden administration is whether it would follow Canada's lead and require all visitors to be vaccinated for COVID-19 before entering the United States, sources briefed on the matter told Reuters.

The White House plans a new round of high-level meetings to discuss the travel restrictions and the potential of mandating COVID-19 vaccines, but no decisions have been made, the sources said.

In early June, the White House launched interagency working groups with the European Union, Britain, Canada, and Mexico to look at how to eventually to lift restrictions.

Businesses in Canada and the United States, particularly the travel and airline industries, pushed for an end to restrictions on non-essential travel between the two countries, which were imposed in March 2020 at the beginning of the pandemic.

Since then, the land border has been closed to all non-essential travel. However, the United States has allowed Canadians to fly in, while Canada has not allowed Americans to do the same.

The United States has continued to extend the restrictions on Canada and Mexico on a monthly basis since March 2020.

Airlines and others have urged the administration to lift restrictions covering most non-U.S. citizens who have recently been in Britain, the 26 Schengen nations in Europe without border controls, Ireland, China, India, South Africa, Iran and Brazil.

(Reporting by David Shepardson; Editing by Steve Orlofsky) ((David.Shepardson@thomsonreuters.com; 2028988324;))