A deal is under way between Russian and US authorities to exchangeUkrainian pilot Nadiya Savchenko for notorious Russian arms dealer Viktor Bout, according to reports.

Ms Savchenko, recently sentenced to 22 years in prison by Russian authorities in a politically charged case, may be exchanged for Mr Bout and Konstantin Yaroshenko, both currently serving lengthy prison sentences in the US for illegal arms sales and drug trafficking, respectively.

In addition to Mr Bout and Mr Yaroshenko, the list reportedly contains Russian citizens “whose activities are not publicly reported,” an Interfax report claimed. The Kremlin has claimed to have no information on such an exchange.

But Alexei Tarasov, a lawyer for Mr Bout, has further fuelled speculation about the proposal.