Russian Deputy Foreign Minister Sergey Ryabkov told ABC News during an exclusive interview in Moscow on Monday that he believes the warring parties are close to a deal.

Ukraine claimed it carried out an underwater drone strike on Dec. 15, the first such attack in maritime warfare, that critically damaged a Russian Kilo-class attack submarine at the Russian port of Novorossiysk,

The European Union is set to lock up Russia’s assets in Europe until Russia ends its war on Ukraine and compensates for the damage.

Ukraine has used long-range drones to attack Russian oil platforms as it expands its strikes on the country's energy sector.

The Russian submarine was allegedly carrying Kalibr cruise missiles, which Russia has used in devastating strikes on critical infrastructure and military targets across Ukraine. The SBU said the submarine was “put out of action” as a result of the blast. The FT could not independently verify the claim.

A senior Kremlin official says Russian police and the National Guard will stay on in eastern Ukraine’s Donbas even if a peace settlement ends the war.

The Kremlin has described Ukraine’s push to join NATO as one of the “root causes” of the conflict. Russia sees an expanding NATO as a major security threat. But NATO’s expansion into the Baltics and other post-Soviet states is driven by a fear that Moscow would one day invade and try to fold them back under its control—as seen in Ukraine.

Ukrainian leaders said Monday they appreciated White House efforts to reach a deal even as significant gaps appeared to remain between the sides.