Mr Bolton, who was the national security adviser under Mr Trump for 17 months from 2018 to 2019, told CBS that the Trump administration had the opportunity to trade Mr Whelan for convicted arms dealer Viktor Bout in 2018.
“The possibility of a Bout-for-Whelan trade existed back then and it wasn’t made, for very good reasons having to deal with Viktor Bout,” he said.
Mr Whelan - a US, Canadian, British and Irish citizen who served in the US Marines from 2003 to 2008 - was arrested in Russia in December 2018.
Mr Whelan, now 52, was working as a director of global security and investigations for BorgWarner and made many business trips to Russia over the years.
In 2020, Mr Whelan was convicted of espionage offences and sentenced to 16 years in prison.
Mr Whelan was originally expected to be part of negotiations, with the US seeking to swap both him and Ms Griner for Bout.
Mr Whelan told CNN he was “greatly disappointed” to learn he was not part of the prisoner swap, saying: “I don’t understand why I’m still sitting here.”. »