WASHINGTON (AP) — President Joe Biden on Friday urged Russia to release Wall Street Journal reporter Evan Gershkovich after the country’s security service arrested him on espionage charges — allegations that the newspaper denies.

“Let him go,” Biden told reporters at the White House on Friday morning when asked about his message to Russia on the arrest of Gershkovich.

Russia’s Federal Security Service has accused Gershkovich, a U.S. citizen, of trying to obtain classified information. It is the first time an American journalist has been detained on accusations of spying since the Cold War. The Journal has said it “vehemently denies” the charges.

The Biden administration said Thursday that it was working to secure consular access to Gershkovich. Asked Friday morning whether he would expel Russian diplomats or journalists in the U.S., Biden responded: “That’s not the plan right now.”

Karine Jean-Pierre, the White House press secretary, called the targeting of U.S. citizens in Russia “unacceptable” and that the administration condemns the detention of Gershkovich "in the strongest terms.”

The Biden administration has also warned U.S. citizens not to travel to Russia, and for Americans in the country now to depart immediately.