Russia's top security agency says it has arrested four Russians accused of making preparations to kill senior Defense Ministry officials on Ukraine's orders.

Russia has arrested four people on suspicion of plotting to assassinate senior defence officials and their families on Ukraine’s orders, the Kremlin’s Federal Security Service (FSB) has said.

President Vladimir Putin said on Thursday there was no time left this year to sign a new Ukrainian gas transit deal, and laid the blame firmly on Ukraine for refusing to extend the agreement that brings gas to Slovakia,

Russia rebuffed incoming US President Donald Trump’s call for an immediate ceasefire in Ukraine, while saying it’s ready to hold negotiations on a long-lasting peace agreement to end almost three years of war.

Ukrainian forces launched an incursion into Russia’s Kursk region in August, a move that undermined Russia’s military prestige and forced it to redeploy troops from eastern Ukraine, where its offensiv

Russia's natural-gas transit deal with Ukraine is set to expire soon, which would cut billions in revenue.

A massive Russian missile and drone barrage on Ukraine's energy infrastructure on Christmas morning was "inhumane," Ukrainian President Zelenskyy said.

U.S. President Joe Biden said on Wednesday he had asked the Defense Department to continue its surge of weapons deliveries to Ukraine, after condemning Russia's Christmas Day attack on Ukraine's energy system and some of its cities.

Russia is willing to work with Donald Trump's incoming administration to improve relations if the U.S. has serious intentions to do so but it is up to Washington to make the first move, Foreign Minister Sergei Lavrov said on Thursday.

North Korean troops are suffering heavy losses in the fighting in Russia’s Kursk region and facing logistical difficulties as a result of Ukrainian attacks.

Ukrainians faced fresh Russian drone and missile strikes on energy infrastructure nationwide on Tuesday night into Christmas Day morning.