Trevor Reed, a 30-year-old from Texas who was jailed in Russia in 2020, was exchanged for Konstantin Yaroshenko, 53, who had been serving a 20-year US prison sentence since 2011.

In footage shown on Russian state television, Yaroshenko emerged from a US plane onto a sunlit airfield, wearing a T-shirt and accompanied by two men in dark suits.

Simultaneously, Reed emerged from a plane opposite with a guard carrying bags.

The two men walked past one other, each on their way to the other's plane.

Russian foreign ministry spokeswoman Maria Zakharova said the exchange was carried out on Wednesday after "a lengthy negotiations process".

State television showed footage of Reed talking to guards in Russian as he left his penal colony, and being escorted onto a plane at Moscow's Vnukovo airport by men in military uniform.

His father Joey Reed told CNN that Trevor was moved to a Moscow prison this week and then flown to Turkey where the swap took place.

In a statement, Reed's family asked for privacy while their son addressed health issues "brought on by the squalid conditions he was subjected to in his Russian gulag".

US President Joe Biden said in a statement the swap required "difficult decisions that I do not take lightly".

"His safe return is a testament to the priority my administration places on bringing home Americans held hostage and wrongfully detained abroad," he added.

Secretary of State Antony Blinken also praised the exchange.

"I am pleased to announce the release of US citizen Trevor Reed, who was wrongfully detained in Russia," he said in a statement.

"We also remain committed to securing the freedom of all US nationals wrongfully detained abroad," he added.

Reed was sentenced to nine years in prison by a Russian court in July 2020 after allegedly attacking police officers while drunk.

As he was being driven to a police station, he allegedly grabbed the arm of a police officer, causing the car to swerve, and elbowed another officer in the abdomen.

- Hunger strike -

Reed pleaded not guilty to the charges, saying he remembers nothing of the incident.

While imprisoned in a penal colony in Russia's Mordovia Republic, some 500 kilometres (300 miles) southeast of Moscow, Reed staged a hunger strike over what he said was a violation of his rights.

His lawyer Sergei Nikitenkov told the Interfax news agency Wednesday that his client did not ask for a pardon.

"He agrees with the fact of the exchange, approves it, but at the same time Trevor does not admit his guilt," he said.

Russian television meanwhile reported that Yaroshenko had already arrived back in the country.

It showed him wiping his eyes as he boarded the plane in Turkey, and being examined by a doctor.

The pilot was arrested in Liberia in 2010 for drug trafficking, then transferred to the United States, where he was sentenced to 20 years in prison in September 2011.

Yaroshenko's lawyer Alexei Tarasov told the RIA Novosti state news agency: "I would call this an Easter miracle," referring to Orthodox Easter.

He said the swap "had been in the works for a very long while".

The Russian's health "leaves much to be desired," the lawyer told state news agency TASS.

In June 2021, Yaroshenko's family sent a letter to Biden requesting a pardon for the jailed pilot.

An exchange of prisoners was on the agenda last June during a summit between Biden and Russian President Vladimir Putin in Geneva.

At the time, Putin hinted that Reed's case could be resolved quickly, calling him a "drunk and a troublemaker".

Another US citizen, Paul Whelan, a former security official at a vehicle parts company, remains in a Russian prison serving 16 years on espionage charges.

Biden referred to his case in a statement, saying: "We won't stop until Paul Whelan and others join Trevor in the loving arms of family and friends."