The United States government said its embassy in Kyiv, the capital of Ukraine, is temporarily closed after it "received specific information" regarding the treat of a possible "significant air attack" on Wednesday.

"The U.S. Embassy in Kyiv has received specific information of a potential significant air attack on November 20," read a security alert released by the embassy.

"Out of an abundance of caution, the Embassy will be closed, and Embassy employees are being instructed to shelter in place.  The U.S. Embassy recommends U.S. citizens be prepared to immediately shelter in the event an air alert is announced," the alert stated.

President Joe Biden recently authorized Ukraine to use long-range U.S.-provided missiles inside Russia. The first attack using such missiles occurred this week.