He strongly denied the charges and proclaimed his innocence, describing himself as a legitimate entrepreneur who didn鈥檛 sell any weapons. Russian officials have cast him as a victim of a nefarious U.S. sting operation and demanded his release for many years.

When Moscow and Washington made a deal to swap him for Griner in December, Bout was held in a medium-security facility in Marion, Illinois and had not been scheduled to be released until 2029.

After his return to Moscow, Bout, 56, quickly became a member of the Kremlin-backed Liberal Democratic Party but has dodged questions about a possible political career.

Bout's art exhibition features a wide gamut of styles and subjects 鈥� from portraits of Soviet-era movie stars to warplanes to animals. Most of his drawings and paintings are done in a realistic manner, but there are also some attempts at abstract composition.

The exhibition includes personal objects, photos and a floor plan of his cell in the U.S. prison.

鈥淲hen you are surrounded by absolutely grey walls topped by barbed wire and when you don鈥檛 see the horizon for a long time, it鈥檚 hard,鈥� Bout said Tuesday at his exhibition. 鈥淭he deprivation of such visual stimuli was a challenge for me. Drawing helped me overcome all that."

He added that his experience taught him that 鈥渓ife can always change drastically.鈥�

鈥淵ou must not give up, you must do everything to the end, and you must remain faithful to your fate despite any difficulties,鈥� Bout said.