Russia formally asked Washington on Thursday to extradite arms smuggler Viktor Bout after a US court jailed him for 25 years for conspiring to supply anti-American guerrillas in Colombia.

Moscow's justice ministry said it sent the petition for Bout to serve his time in Russia after getting written permission from Viktor Bout's wife Alla, a condition it said was imposed by justice officials in the United States.

Bout denies trying to organise the 2008 sale out of a Bangkok hotel room for which he was convicted and accuses US authorities of proposing the deal to him themselves as an excuse to arrest him in a sting operation.

The 45-year-old, accused in the past two decades of selling arms to despots embroiled in some of the world's bloodiest conflicts, was the inspiration for the arms smuggler played by Nicolas Cage in "Lord of War" (2005), and has been dubbed the "Merchant of Death".

Russia has denounced Bout's sentencing as "baseless and biased", noting that it could further undermine relations that are already straining from repeated expression of US concern about President Vladimir Putin's rights record.