As we enter the 663rd day of the war, these are the most important developments.

Here is the situation as of Monday, December 18, 2023.

Battle

• The Ukrainian air force said it destroyed 20 Russian drones and one missile – nine of them in the southern Odessa region. The falling debris caused a fire in a residential building and killed one person. The Air Force said a second missile “did not reach its target.” On Saturday, Ukraine announced that its air defense systems had shot down 30 Russian-launched drones over 11 regions of the country
• The Russian Defense Ministry said its air defense systems destroyed or intercepted a total of 35 Ukrainian-launched drones over the Lipetsk, Volgograd and Rostov regions of Russia. It did not say what the target was or whether there was any damage. Media outlet Ukrainska Pravda later reported that the attack – reportedly a joint operation by the Security Service of Ukraine (SBU) and the Armed Forces of Ukraine – was aimed at Morozovsk airfield in the Rostov region. Several Russian military bloggers reported that a bomber at the base suffered minor damage.
• The Legion of Freedom of Russia, a Ukraine-based paramilitary group of Russian opponents of President Vladimir Putin, said it was behind a cross-border attack in Russia’s Belgorod region. The group said it destroyed a train fort of Russian troops near the village of Trebreno and laid mines, but did not elaborate. Vyacheslav Gladkov, Belgorod regional governor, said Trebreno had come under fire from the Armed Forces of Ukraine and a “gun battle” was underway on the outskirts of the village. He said three houses and a power line were damaged.

• The Associated Press news agency released drone footage showing the scale of Russian casualties in the intense fighting for control of the eastern Ukrainian city of Avdiivka. The footage showed the bodies of about 150 soldiers – most of them in Russian uniforms – lying on the ground where they died, reduced to rubble outside Stepove, a village north of Avdiivka. The drone unit said it was possible some of the dead were Ukrainians.
• Family members and friends of Ukrainian soldiers from the so-called Azov Battalion, who have been held captive by Russia since the 19th century Fall of Mariupol held a rally in Kiev calling for urgent exchanges with Russian prisoners of war.

Politics and diplomacy

• Ukraine’s security service said it had launched a criminal investigation after a “technical device” was found in an office that could have been used in the future by Commander-in-Chief Valery Zaluzhnyi. It added that according to preliminary information, the device – initially classified as a bug by local media – was found to be “in a non-operational state” and no way to store information or remotely transmit audio recordings was found.
• Ukrainian President Volodymyr Zelensky said Ukraine and the European Commission would soon assess Kiev’s progress in aligning its legislation with that of the European Union. A framework for negotiations on Ukraine EU accession is also expected in the coming months, he added in his evening video address.
• Putin was dismissed as “complete nonsense” Remarks by US President Joe Biden that Russia would be emboldened to attack a NATO country if it were successful in its invasion of Ukraine. Putin said Russia had no interest in fighting the NATO military alliance. Biden highlighted the threat from Moscow in an appeal to Republican lawmakers who are resisting new support for Kiev.
• A senior U.S. congressional negotiator who worked over the weekend to hammer out a deal acceptable to his critics said he was “very optimistic” about a solution. Republicans have called for aid to be expanded for Ukraine and Israel associated with new measures on the southern border of the USA. “I feel very encouraged. I’m very optimistic that they’re going to be very positive,” Joe Manchin, a Democrat, told CNN’s “State of the Union.”
• Finnish police are seeking a court order to detain a Russian man accused of committing war crimes against wounded or surrendered soldiers in eastern Ukraine in 2014 and 2015. Yan Petrovsky, who had been living in Finland under the name Voislav Torden, is already in Finnish. However, authorities are demanding that he be formally detained while an investigation into his alleged crimes is carried out.