The blocking of Russian social networking websites in Ukraine is a measure to counter propaganda, Ukrainian President Petro Poroshenko said.

"Ukraine has been living in war conditions for three years now, amid Russian aggression against our independent country. The important part of that war is a hybrid war waged by Russia," Poroshenko said at a press conference in Strasbourg on Wednesday.

"Enormous propaganda budgets are being allocated to destabilize the situation both inside Ukraine and within Europe," Poroshenko said.