The crisis in the east of Ukraine cannot be resolved by force, White House press secretary Josh Earnest has said at a press conference.

"With regard to the provision of military assistance to Ukraine, the president [Barack Obama] does not want to do this for the reason that the problem cannot be used by military means. This conflict must be resolved by diplomatic means," he said.

In addition, according to Earnest, "the longer the sanctions will work, the more impact they will have on the economy of Russia."

"There is an element of chaos in the Russian economy, whose situation is getting worse every day," he said.

According to the White House representative, Russia will increasingly feel the effects of the measures imposed on it, therefore "there is still the possibility that it will revise its strategy in Ukraine."