"We hope the Russian Federation will see Paul's release - through clemency or some other means - as an opportunity to help rebuild the US-Russia relationship", David Whelan said.
The prosecutor asked the Moscow City Court on Monday to sentence Paul Whelan to 18 years in a high-security prison.
"The request shocked the defence lawyers, who are seeking an acquittal", David Whelan said.
At the end of 2018, the Russian authorities detained Paul Whelan, who is also a citizen of the United Kingdom, Canada and Ireland, on charges of espionage. If convicted, he faces up to 20 years in prison.
Paul has maintained that he is innocent and has insisted that he came to Russia to attend a friend's wedding. According to information provided to the Russian court, Paul had been visiting Russia regularly since 2007.