WASHINGTON (Reuters) - The United States said on Thursday it will extend restrictions barring non-essential travel at land borders with Canada and Mexico through Dec. 21. The restrictions were first put in place in March to control the spread of COVID-19. Reuters reported Wednesday they were expected to be extended for another 30 days beyond the prior Nov. 21 expiration date. Acting Homeland Security chief Chad Wolf said on Twitter the United States is “working closely with Mexico & Canada to keep essential trade & travel open while also protecting our citizens from the virus.” Canada’s Minister of Public Safety and Emergency Preparedness Bill Blair confirmed the extension, saying the government’s “decisions will continue to be based on the best public health advice available to keep Canadians safe.” Stringent measures were going into effect across the United States this week as the U.S. COVID-19 death toll passed a quarter million, the highest in the world. More than 20 states have passed sweeping restrictions this month. Statistics Canada said last month that August visits to Canada by car by U.S. travelers were down 95.7% in August and the number of U.S. travelers to Canada by plane fell by 97.9%. The United States still has in place entry bans on nearly all non-U.S. citizens who recently were in China, the United Kingdom, Ireland, Brazil, Iran and countries in the so-called Schengen border-free area of Europe.The Trump administration has held extensive talks with various countries about modifying those restrictions to allow for the resumption of some travel with COVID-19 testing before departure and after arrival. Nearly all of Europe still bans most U.S. travelers, while the UK allows Americans to visit but requires a two-week quarantine upon arrival.