Nazarbayev made the remarks during a news conference in Kiev on Monday after a meeting with his Ukrainian counterpart, Petro Poroshenko.
“I call on Russia and Ukraine to think about finding compromise,” he said, adding, “This situation is nonsense and should not be taking place.”
The reunification fueled pro-Russia protests in the eastern regions of Ukraine. The Western-backed Kiev government launched military operations in mid-April to silence the protests.