The closure of the Canada-U.S. border has been extended to Feb. 21.

The border has been closed to all nonessential traffic since March. The closure agreement is reviewed by U.S. and Canadian government authorities each month.

ABC News’ Christine Theodorou contributed to this report.

U.S. Health and Human Services Secretary Alex Azar said the federal government will no longer hold back COVID-19 vaccine doses and is now recommending states inoculate anyone 65 and older as well as those under the age of 65 who have two or more conditions or illnesses.

"This is just a staging and moving to the next phase on the vaccine program. We've had so much success with quality and predictable manufacturing and almost flawless distribution of the vaccine, but we have seen now that the administration in the states has been too narrowly focused," Azar told ABC News chief anchor George Stephanopoulos in an interview Tuesday on Good Morning America.

"So, what are we doing? Three things. First, We have already made available every dose of vaccine," he said. "So we had been holding back second doses as a safety stock. We now believe that our manufacturing is predictable enough that we can ensure second doses are available for people from ongoing production. So everything is now available to our states and our health care providers."

"Second, we are calling on our governors to now vaccinate people age 65 and over and under age 65 with a comorbidity, because we have got to expand the group," he continued. "We've already distributed more vaccine than we have health care workers and people in nursing homes."

"Third, we've got to get more channels of administration," he added. "We've got to get it to pharmacies, get it to community health centers, and we are here and we will deploy teams to support states doing mass vaccination efforts if they wish to do so. It has been overly hospitalized so far in too many states."

As of 9 a.m. ET on Monday, more than 25 million COVID-19 vaccine doses have been distributed nationwide but fewer than 9 million people have received their first dose, according to data provided by the U.S. Centers for Disease Control and Prevention.

The European Medicines Agency (EMA) said Tuesday that it has received an application for conditional marketing authorization for the COVID-19 vaccine developed by England's University of Oxford and British-Swedish pharmaceutical giant AstraZeneca.

Conditional marketing authorization is the process used to speed up the approval of treatments and vaccines amid public health emergencies. The EMA said the assessment of the Oxford/AstraZeneca vaccine "will proceed under an accelerated timeline," and that an opinion on whether to issue an authorization could be announced by Jan. 29.

"If EMA concludes that the benefits of the vaccine outweigh its risks in protecting against COVID‑19, it will recommend granting a conditional marketing authorisation," the agency said in a statement Tuesday. "The European Commission will then fast-track its decision-making process with a view to granting a conditional marketing authorisation valid in all EU and EEA Member States within days."

Russia has extended its suspension of air travel with the United Kingdom through Feb. 1 amid growing concerns over a new, more contagious variant of the novel coronavirus.

"For the purpose of protecting public health, the restrictions have been extended through 11:59 p.m. on February 1, 2021," Russia's coronavirus response headquarters said in a statement Tuesday.

The ban was first imposed in late December.

The move comes after Russia confirmed its first cases of a new, highly infectious strain that is thought to have emerged in England late last year. The variant, called B117, is currently prevalent in London and other parts of southeastern England, and has since spread to more than a dozen other countries.

With more than 3.3 million confirmed cases of COVID-19, Russia has the fourth-highest tally of diagnosed infections in the world, followed by the U.K., according to a real-time count kept by Johns Hopkins University.

Russia's coronavirus response headquarters confirmed 22,934 new cases and 531 additional deaths from the disease on Monday, bringing the cumulative total to 3,448,203 cases with 62,804 deaths.

ABC News' Tanya Stukalova contributed to this report.

Researchers at Ohio State University's Wexner Medical Center said Wednesday that they've have identified two new variants of the virus that causes COVID-19.

The first variant, which was found in just one person, contains a mutation that's similar to a mutation seen in the variants from the U.K. and South Africa, but it arose independently in the U.S., the researchers said. It is not known if it is more easily transmissible.

The second newly identified variant was found in about 20 patients in Columbus and also arose independently in the U.S., the researchers said. It does not contain any mutations in common with variants identified in the U.K. or South Africa, they said. Scientists said they found cases of this variant with increased frequency during late December, which could imply that it's more easily transmissible, but they emphasized that more studies are needed.

Peter Mohler, a co-author of the study and chief scientific officer at the Wexner Medical Center, said Wednesday, "we’re not ready to overreact," stressing, "this is very normal for a virus to mutate."

ABC News' Sony Salzman contributed to this report.