The European Union and the United States should join in the negotiations to eliminate the conflict in Donbas, otherwise, in a face-to-face situation, Russia may outplay Ukraine, Prime Minister of Ukraine Arseniy Yatseniuk has said.

"I am for the Geneva format of the negotiations in which the United States, the EU, Ukraine and Russia are involved. We are not strong enough to negotiate on a bilateral basis, Russia will outplay us, Putin desires to get yet another frozen conflict," said Yatseniuk at 11th Annual Meeting of Yalta European Strategy (YES) on Saturday in Kyiv.

According to him, the president of Russia wants to get not just Donetsk and Luhansk regions, but the whole of Ukraine, as Putin can't accept its European ambitions and dreams to restore the USSR.

"The first step was the annexation of Crimea, the second – the creation of a frozen conflict in Donbas, and third step will be a corridor via Odesa to Transdniestria," the premier said.

Yatseniuk also added that the successful reforms in Ukraine are possible only when the war in the east of the country is over.

"The key priority not only for Ukraine, but for the entire world is to deter Russia and stop the war. This is the key prerequisite for further reforms. If we manage to stop the war, if we manage to deter Russia, we'll have a chance to engage international investors since, you know how difficult it is to attract them when Russian tanks and artillery are already in your country, [and how difficult it is] to restore confidence in local investors and positively focus on the reforms our country needs," Yatseniuk said.