KYIV, May 8 – Russia seeks to destabilize Ukraine and return it to the Soviet Union, President Petro Poroshenko said.

"He [Russian President Vladimir Putin] wants to return the Soviet Union. Poroshenko answered in an interview to the question what is considered to be the biggest catastrophe of the 20th century – it is not World War II, not Hiroshima, not Chornobyl, but the collapse of the USSR. This is his way of thinking," Poroshenko said in an interview with CBS News, answering the question of what Putin is trying to achieve in Ukraine and whether he wants a weak country on the Russian border," the presidential press service said on Tuesday.

According to Poroshenko, the Russian president is trying to take Ukraine back: "Yes, to win back, and to return the USSR or the Russian Empire, as you prefer."

The head of state said that Ukraine has confirmed data about the presence of regular Russian troops in the occupied part of Donbas.