WATCH: White House press secretary Jen Psaki discusses Russian prisoner swap

Press secretary Jen Psaki on Wednesday explained the White House’s rationale for entering into an unexpected prisoner exchange between the United States and Russia in a time of high tensions, trading a Marine veteran jailed by Moscow for a convicted Russian drug trafficker serving a long prison sentence in America.

Watch the briefing in the player above.

“It is a huge moment today,” Psaki said, “that speaks to President Biden’s commitment to bring home Americans held hostage and wrongfully detailed around the world.”

The deal announced by both countries involving Trevor Reed, an American imprisoned for nearly three years, would have been a notable diplomatic maneuver even in times of peace. It was all the more surprising because it was done as Russia’s war with Ukraine has driven relations with the U.S. to their lowest point in decades.

The U.S., for its part, returned Konstantin Yaroshenko, a Russian pilot who’d been serving a 20-year federal prison sentence in Connecticut for conspiracy to smuggle cocaine into the U.S. after he was arrested in Liberia in 2010 and extradited to the U.S. The Justice Department has described him as “an experienced international drug trafficker” who conspired to distribute thousands of kilograms of cocaine around the world.

Despite Reed’s release, other Americans remain jailed in Russia, including WNBA star Brittney Griner and Michigan corporate security executive Paul Whelan.

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President Joe Biden, who met in Washington with Reed’s parents last month, trumpeted Reed’s release and noted without elaboration that “the negotiations that allowed us to bring Trevor home required difficult decisions that I do not take lightly.” The Russian foreign ministry described the exchange as the “result of a long negotiation process.”

Reed, a 30-year-old former Marine from Texas, was arrested in the summer of 2019 after Russian authorities said he assaulted an officer while being driven by police to a police station following a night of heavy drinking. He was later sentenced to nine years in prison, though his family maintained his innocence and the U.S. government described him as unjustly detained and expressed concern about his declining health.

A lawyer for Yaroshenko, who last year sought a reduced prison sentence because of Yaroshenko’s vulnerability to COVID-19, did not immediately return an email seeking comment Wednesday.

Psaki also said the United States had been in touch with Poland and Bulgaria in the last 24 hours, as Russia announces it cut off natural gas to the two NATO members and threatened to do the same to other countries, dramatically escalating its standoff with the West over the war in Ukraine. European leaders decried the move as “blackmail.”

Psaki said the U.S. had been working for months to diversity natural gas supplies to Europe.

A day after the U.S. and other Western allies vowed to speed more and heavier weapons to Ukraine, the Kremlin used its most essential export as leverage against two of Kyiv’s staunch backers. Gas prices in Europe shot up on the news.

The tactic could eventually force targeted nations to resort to gas rationing and could deal another blow to economies suffering from rising prices. At the same time, it could deprive Russia of badly needed income to fund its war effort.

Western leaders and analysts portrayed the move by the Kremlin as a bid to both punish and divide the allies so as to undermine their united support for Ukraine.