As Russian President Vladimir Putin explores a potential peace settlement to end the war in Ukraine, hawkish anti-Western nationalists at home are waging a campaign to keep the conflict going.

A meeting between President Trump and Russian President Vladimir Putin is the “only way” to move forward with talks on ending the war in Ukraine, Secretary of State Marco Rubio said Thursday.

(Reuters) - Kremlin leader Vladimir Putin announced late on Wednesday Russia's delegation to direct talks with Ukraine on settling the war, including an adviser to the president, a top diplomat and senior military and intelligence officials.

On May 5, Ukraine's National Guard released a clip it said showed how it used drones to rebuff a Russian motorcycle onslaught of troops trying to plant their flag on the ruins of a building. The video ends with the bodies of wounded or dead Russian soldiers lying next to their motorcycles.

Eastern Ukraine has been contested territory since 2014, when Russian-backed fighters seized large swathes of the eastern Donetsk and Luhansk regions. Russia had already seized the southern peninsula of Crimea in February 2014 before annexing it soon afterwards.

Moscow's goal in the expected peace talks with Ukraine in Istanbul is achieving "sustainable peace" by addressing the "root causes of the conflict" rather than a ceasefire, Russian Foreign Minister Sergey Lavrov said on May 15.

The war in Ukraine could escalate into a direct confrontation between the U.S. and Russia, according to the Pentagon. General Gregory Guillot, the head of the U.S. Northern Command (USNORTHCOM) and North American Aerospace Defense Command (NORAD) issued the warning to the U.S. Senate Armed Services Committee.