A decision on Ukrainian pilot Nadia Savchenko's handover from Russia to Ukraine may be made only after Kyiv makes an official request for that and after the sentence handed down on her on Tuesday takes legal effect, a Russian law enforcement source told Interfax.

"Savchenko's handover or exchange has been discussed this or that way at various levels. However, a decision on this may be made only if Kyiv forwards an official request for that to Moscow and after the sentence takes legal effect, that is, ten days after its pronouncement," the source said.

"In addition, Ukraine's recognition of her conviction is among the preconditions for her handover," the source said.