However, he added that he doesn't know how much further the forces would go, but that he expects the attack to return to Kyiv.

Read here Russia has started the battle for Donbas, we will fight, – Zelenskyy

"We expect everything and anything, especially in regards to the capital. Of course, we're waiting for them to come back. We're expecting that," Klitschko told. "If you invade the country, obviously you're aiming at the capital of the country."

Help is "crucially" needed, he continued.

"We can only defend our country during the war with the weapons. There is no other way. Otherwise, this senseless killing of the civilian population and destruction of our infrastructure is going to continue," Klitschko said. "I don't think we need any military. We just need weapons to defend ourselves."