The U.S. ambassador to Russia on Wednesday visited Paul Whelan, a former Marine serving a 16-year sentence for espionage, charges he denies. Ambassador Lynne Tracy emphasized to Whelan during the meeting that the Biden administration was committed to securing his release, the State Department said.

Whelan was arrested in 2018 and convicted in 2020. Both Whelan and the U.S. government deny he is a spy. The U.S. says Whelan and Wall Street Journal reporter Evan Gershkovich are both wrongfully detained.

“Ambassador Tracy did meet with Paul Whelan earlier today. It was a consular visit,” State Department spokesman Matthew Miller told reporters at a briefing.

“We believe Paul continues to show tremendous courage in the face of his wrongful detention. Ambassador Tracy reiterated to him that President [Joe] Biden and Secretary [of State Antony] Blinken are committed to bring him home,” Miller said.

Tracy has also met with Gershkovich three times in recent months. Like Whelan, he denies accusations that he was working undercover as a spy gathering intelligence against Russia.

Miller wouldn’t address rumors of a potential prisoner swap involving Vadim Krasikov, a convicted Moscow assassin imprisoned in Germany, for Whelan.

The Biden administration has negotiated two prisoner swaps with Russia. The first involved freeing former Marine Trevor Reed in April 2022 in exchange for a Russian pilot and drug smuggler. The second involved WNBA basketball star Brittney Griner, who was released in December 2022 in exchange for international arms dealer Viktor Bout, known as the “Merchant of Death.”