Ukrainian military pilot Nadiya Savchenko arrived home in Kiev on Wednesday after nearly two years in a Russian jail, part of a prisoner swap in which two Russians held in Ukraine were returned to Moscow.

Handing over Savchenko, whose release had been demanded by Western governments and who has become a national hero in Ukraine, is likely to ease tensions between Moscow and the West a few weeks before the European Union decides whether to extend sanctions against Russia.

"A presidential plane with Ukraine's hero Nadiya Savchenko has landed," Ukrainian President Petro Poroshenko said in a post on Twitter.

In Moscow, Kremlin spokesman Dmitry Peskov said that Savchenko, who while in Russian jail was elected a member of the Ukrainian parliament, was granted a pardon by Russian President Vladimir Putin to allow her to leave jail and return home.

Peskov also said that the two Russians, Alexander Alexandrov and Yevgeny Yerofeyev, were now back in Russia, having landed at Moscow's Vnukovo airport on a special flight from Kiev.

Ukraine accused them of being Russian special forces officers fighting in eastern Ukraine, though Moscow has never acknowledged the two were following its orders.