Vehicles drive past the embassy of the U.S. in Moscow
Vehicles drive past the embassy of the U.S. in Moscow, Russia August 21, 2017. Reuters

President Joe Biden's nominee to be ambassador to Russia, Lynne Tracy, pledged on Wednesday to make the release of detained Americans a priority if she is confirmed to one of most important, and challenging, U.S. diplomatic posts.

"The plight of U.S. citizens detained in Russia will be a top priority for me," Tracy said during her confirmation hearing before the Senate Foreign Relations Committee, which took place as Washington supplies weapons and other support for Ukraine as it battles Russia's nine-month-long invasion.

Tracy, a career diplomat and current ambassador to Armenia, promised to visit detained Americans, including basketball star Brittney Griner and former Marine Paul Whelan.

Biden announced Tracy's nomination in September, weeks after the departure of John Sullivan, who had been appointed by former Republican President Donald Trump and was ambassador as Russia's invasion of Ukraine plunged relations to depths not seen since the Cold War.

"It's difficult to imagine a more challenging assignment for a career diplomat," said Democratic Senator Bob Menendez, the committee's chairman.

It was not immediately clear when Tracy would assume the post, if she is confirmed as Russia must agree to accept her.

Moscow has an ambassador in Washington, Anatoly Antonov.

Tracy served as deputy chief of mission in Moscow from 2014 to 2017. A Russian speaker, she would be the first woman to serve as U.S. ambassador to Russia.

Some committee members indicated that they expected she would be confirmed by the full Senate. "She's tested, she's eminently qualified," said Senator Rob Portman, who represents Tracy's home state of Ohio and introduced her at the hearing.

Senator Chris Van Hollen asked Tracy how talks were going with India and other countries about a proposed price cap on Russian oil. "We have having conversations across the globe," she said, adding "we continue to encourage major purchasers of Russian energy" to join the effort.

Western governments want to set a maximum purchase price for Russian oil on the world market to limit Moscow's ability to raise money for its war on Ukraine.