Russia said Monday that it recognized the outcome of the referendum signed for the secession of two cities in eastern Ukraine, while the European Union, or EU, said that it is prepared to impose more sanctions against Russia if it interferes with Ukraine's elections scheduled for May 25.

Pro-Moscow rebels, who carried out the referendum Sunday despite Russian President Vladimir Putin’s call to postpone it, claimed that more than 90 percent of the local population in the eastern Ukrainian regions of Luhansk and Donetsk had chosen to secede from Ukraine, prompting the nation's interim president, Oleksandr Turchynov, to accuse Russia of working to overthrow legitimate state power, even as clashes resumed in the Luhansk region Sunday night.

“In Moscow, we respect the will of the people of the Donetsk and Luhansk regions and are counting on practical implementation of the outcome of the referendum in a civilized manner, without any repeat of violence and through dialogue,” the Kremlin said in a statement, according to the Moscow Times.

The EU said Monday that it is ready to extend sanctions against Russia and that it will target companies and individuals who assisted in Russia's annexation of the Crimean peninsula.

"These attempts at referendums have zero credibility in the eyes of the world, they are illegal by anybody's standards,” British Foreign Secretary William Hague said Monday in Brussels, after meeting other leaders from the EU, according to Reuters, adding: "We need to send a clear message that what we have seen until now is completely unacceptable."

Clashes began Sunday night, according to Ukraine’s interior minister Arsen Avakov, who clarified that there were no injuries reported and added that the administration in Kiev would continue to fight the "terrorists."

“The information war that they are waging against us in the Donbass (east) is more dangerous than a bullet. We must answer back ... the enemy fears this more than special forces," Avakov said, on his Facebook page.

Meanwhile, Turchynov said, according to Interfax Ukraine: "The farce that terrorists and separatists call a referendum is nothing more than a propaganda covering of murders, kidnappings, violence and other serious crimes," adding: “The administration will hold a dialogue with those in eastern Ukraine whose hands are not stained with blood and who are ready to defend their goals and convictions using legal methods.”