U.S. customs officers speak to people in a car next to a sign that says the U.S. border is closed on March 22, 2020 at the U.S.-Canada border in Lansdowne, Ontario.

Lars Hagberg | AFP | Getty Images

The U.S. will continue to enforce coronavirus-related restrictions on unnecessary travel across U.S. land borders through June 21, the Biden government said Thursday.

“We are working closely with Canada and Mexico to safely relax restrictions as conditions improve,” the Department of Homeland Security said on Twitter.

Substantial trade and travel are still allowed, the DHS tweeted.

The DHS tweet did not make it clear whether the agency expected to relax these restrictions immediately after June 21, or whether it would simply re-evaluate the need for those restrictions at that point. The DHS did not immediately respond to requests for clarification.

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The DHS introduced cross-border travel restrictions under then-President Donald Trump on April 20, 2020, more than a month after the World Health Organization declared the virus had grown into a pandemic.

The government’s decision to hold restrictions on for another month was announced amid a decline in Covid infections and deaths in the US, which has given more than 277 million vaccine doses, with 47% of the population having received at least one injection to date.

The Centers for Disease Control and Prevention last week changed their guidelines on masks, telling Americans that in most cases they will no longer need to wear preventative face coverings after being fully vaccinated.

But President Joe Biden and his health officials are still warning that the nation has not yet got rid of the pandemic, especially as highly transmissible variants of Covid are emerging in the US and are proliferating in other countries