OTTAWA (Reuters) – Canada and the United States on Tuesday extended a land-border closure for non-essential travelers, and air passengers arriving in Canada will continue to be tested for COVID-19 ahead of a hotel quarantine period, authorities said.

The land-border restrictions, imposed in March 2020, have been extended to May 21. Now in place for 13 months, they are being renewed month by month. Mexico said late on Monday it was maintaining some of its border restrictions, too.

“We are guided by science and public health data and engaged in discussions with Canada and Mexico about easing restrictions as health conditions improve,” the U.S. Department of Homeland Security said on Twitter.

The restrictions have hit many border communities and businesses hard. Many U.S. lawmakers have urged loosening the restrictions or setting a road map to resuming normalized travel.

Canada continues to lag the United States on vaccinations, and much of the country is now fighting a virulent third wave of the disease with school and business closures.

Canada’s required three-day hotel quarantine following testing at airports, which was introduced as a temporary measure to discourage spring break travel, was also extended to May 21, health authorities said.

Canada began testing international air arrivals in February, and requiring them to pay for a three-day hotel quarantine themselves, a measure criticized by airlines hit hard by the pandemic.

Air travelers are also are required to have had a test within three days of departure. If the airport text comes back negative, they can finish a 14-day quarantine at home.

However, data obtained by Reuters showed that more than 1,000 passengers, or 1.5% of those who arrived from Feb 22 to March 25, tested positive for COVID-19, casting doubt over a broad easing of restrictions before the summer travel season.

(Reporting by Steve Scherer in Ottawa and David Shepardson in Washington; Editing by Bernadette Baum)