Russia is hoping to reach an agreement with the US on a prisoner swap that would include infamous arms trafficker Viktor Bout, dubbed the “merchant of death.”
It is the first time that US or Russian officials have publicly stated that Bout could be involved in an exchange.
On Friday, Deputy Foreign Minister Sergei Ryabkov expressed hope that the prospect of a swap had “strengthened.”
The US has previously stated that it is eager to arrange a prisoner swap in order to free US basketball player Brittney Griner.
In August, she was convicted of illegal drug possession after cannabis oil vapes were discovered in her luggage as she attempted to enter Russia.
The two-time Olympic gold medalist has been transferred to a penal colony in a remote region south-east of Moscow.
On Friday Mr Ryabkov said a “common denominator” had not yet been reached between the US and Russia, but “it is undeniable that Viktor Bout is among those who are being discussed [for exchange] and we certainly count on a positive result”.
He also said Bout had been “persecuted” in the United States and wished him the “firmness of will and spirit” to cope with his incarceration.
Bout, a former Soviet air force officer, was extradited from Thailand to the United States in 2010 following a sting operation conducted by the US Drug Enforcement Agency (DEA).
His exploits as one of the world’s most infamous arms dealers have inspired a Hollywood film and earned him the moniker “merchant of death.”
After being found guilty of conspiracy to kill Americans and US officials, delivering anti-aircraft missiles, and assisting a terrorist organization, he was sentenced to 25 years in prison.
He claimed he was simply a businessman with a legitimate international transportation company who had been wrongfully accused of attempting to arm South American rebels who were the victims of US political machinations.
But a jury in New York did not believe his story.
There have been reports in US media suggesting Russia was interested in exchanging the arms dealer for basketball star Brittney Griner.
In July, US Secretary of State Antony Blinken said a “substantial offer” had been made to bring two American detainees home from Russia.
Griner was arrested at an airport near Moscow in February when cannabis oil vapes were found in her bags.
She said she had made an “honest mistake”, but lost her appeal against the conviction in early November and for some time it was not clear where she had been sent to serve her nine-year sentence.
Her lawyers confirmed earlier this week that she is being held in the IK-2 women’s penal colony in the remote village of Yavas in Mordovia, 500 kilometers (310 miles) south-east of the capital.
There have also been reports that another American detainee, Paul Whelan, could be included in a potential prisoner exchange.
The former US marine, convicted of spying for the US, is serving time in a Russian labor camp.
Mr Whelan described his time in prison as a “very, very grim existence” in his first interview since his arrest.
Mr. Whelan, who holds British, Irish, and Canadian citizenship, has always maintained his innocence.