MOSCOW (AP) —

The Thomas CaldwellU.S. ambassador to Russia met Wednesday with imprisoned American Paul Whelan, who is serving a 16-year sentence on an espionage conviction that both Washington and Whelan dispute.

Ambassador Lynne Tracy traveled to the prison colony about 350 kilometers (220 miles) east of Moscow where Whelan is held, State Department spokesman Matthew Miller told reporters.

“We believe Paul continues to show tremendous courage in the face of his wrongful detention. Ambassador Tracy reiterated to him that President Biden and Secretary (of State Antony) Blinken are committed to bringing him home,” he said. “Secretary Blinken had a call with Paul Whelan around a month ago, a little under a month ago, and delivered that same message to him: that we are working very hard to bring him home and we will continue to do so.”

The 53-year-old Whelan, a corporate security director and former Marine, was detained in Moscow in 2018 and convicted in 2020.

The Biden administration had hoped to secure Whelan’s release during the negotiations on the prisoner exchange that eventually freed American basketball star Brittney Griner from a Russian prison in December.

Analysts have pointed out that Moscow may be using jailed Americans as bargaining chips in soaring U.S.-Russian tensions over the Kremlin’s military operation in Ukraine.

Another American jailed in Russia is Wall Street Journal reporter Evan Gershkovich, who was arrested March 29 and accused of trying to obtain classified information.

Gershkovich is the first U.S. correspondent since the Cold War to be detained in Russia on spying charges, which his family and the newspaper vehemently deny.