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 U.S. has agreed to provide unspecified security guarantees to Ukraine as part of a peace deal to end Russia's nearly four-year war, and more talks are likely this weekend, U.S. officials said Monday following the latest discussions with Ukrainian President Volodymyr Zelenskyy in Berlin.

The GUR said that the modified drone contains foreign-made parts produced by companies in the US, UK, Germany, Switzerland, China, Japan, and Taiwan. Kyiv has frequently identified components in Russian weaponry sourced from these countries, some of which are among Ukraine's closest partners.

The latest overnight attacks come as US envoy Steve Witkoff prepares to hold more talks with Ukraine's president.

Russia is pushing to take over all of eastern Ukraine's Donbas region, where one resident tells NPR that she feels her "life depends on how our guys at the front hold on."

Ukrainian drone attack in southwestern Russia killed two people as parts of Ukraine went without power after Russian assaults on energy sites hours before peace talks were to restart in Germany.

Ukraine’s domestic security service, the SBU, said Monday that it struck a Russian submarine in the Black Sea port of Novorossiysk, causing critical damage to the vessel and effectively disabling it.