Ukraine has rejected Georgia's request for the extradition of its former president, Mikhail Saakashvili, who is facing a criminal probe at home.

The Ukrainian Prosecutor-General's office said in Wednesday's statement that Saakashvili could face political persecution in Georgia if he is extradited.

Saakashvili, who was president in 2004-2013, left Georgia in the face of abuse of power accusations leveled by his political foes. Saakashvili's United National Movement has been in opposition since losing the 2012 parliamentary election to a party founded by billionaire Bidzina Ivanishvili, who made his fortune in Russia.

Ukrainian President Petro Poroshenko has appointed Saakashvili the head of his advisory council.

Saakashvili has dismissed the accusations against him as a political vendetta by Ivanishvili, accusing him of serving Moscow's interests.