Ukrainian President Petro Poroshenko has said he rejects statements by politicians who say the question of Crimea's return to Ukraine has been resolved.

"I strongly reject statements by those who speak about Crimea as an 'accomplished fact,'" he said at a plenary session of the Parliamentary Assembly of the Council of Europe (PACE) in Strasbourg on Wednesday.

Poroshenko said that the PACE rostrum had been created not for appeals for pacification, "nor for appeals to trade territories for money, oil, or gas."

"This rostrum was created to protect our foundations, our values, and our principles… This is a necessity that is required today," Poroshenko said.

He also quoted former British Prime Minister Winston Churchill: "Either we shall prove our worth and weight and value to Europe or we shall fail."

According to Poroshenko, it is precisely today that Moscow is pushing Europe towards the same reality that concerned Churchill almost 70 years ago.

"Therefore, the preservation and strengthening of our unity, solidarity, and stability remains the key to our success. Only on the basis of respect for the sovereignty and territorial integrity of Ukraine can we achieve peace and stability in Europe. I and everyone in this hall believe that Ukraine wants peace. As head of state, I want peace for Ukraine and Europe," Poroshenko said.