Russian forces are conducting a new cognitive warfare campaign through limited cross-border attacks across a broad part of the previously dormant northern frontline in Sumy and Kharkiv oblasts. Ukrainian authorities reported on December 20 and 21 that Russian forces entered Hrabovske, Sumy Oblast (a small rural village southeast of Sumy City along the international border) overnight on December 19 to 20, and the Russian Ministry of Defense (MoD) and other Russian sources claimed on December 20 and 21 that elements of the Russian had seized Hrabovske and Vysoke (immediately south of Hrabovske).[1] Ukrainian Armed Forces Main Communications Directorate Spokesperson Captain Dmytro Lykhovyi stated on December 21 that Ukrainian forces withdrew from several positions near Hrabovske and are working to stabilize the area.[2] Available evidence indicates that Russian forces have likely seized Hrabovske. A source reportedly affiliated with Ukrainian military intelligence reported that Hrabovske is a contested “gray zone” that neither Russian nor Ukrainian forces currently control, however.[3] Russian milbloggers reported that Russian forces advanced across the international border into Hrabovske under the cover of night and fog and also entered Ryasne (immediately west of Hrabovske).[4] The Ukrainian Joint Forces Task Force acknowledged on December 21 that fighting continues for Hrabovske but rejected reports that Russian forces had entered Ryasne.[5] Russian sources credited elements of the 34th Motorized Rifle Brigade (49th Combined Arms Army [CAA], Southern Military District [SMD]) with the seizure of Hrabovske.[6]
Russian forces also conducted a geographically separate across-border attack against another small rural border village in Kharkiv Oblast. Geolocated footage published on December 21 shows Russian infantry (about two squads totaling around 15 infantry) attacking Ukrainian positions in northern Sotnytskyi Kozachok (northwest of Kharkiv City, about 15 kilometers east of Grayvoron, Belgorod Oblast, and less than half a kilometer from the international border), and a Ukrainian drone unit operating in the border area reported that Ukrainian forces repelled the assault.[7]
These two cross-border attacks likely intend to advance the Kremlin’s cognitive warfare campaign to convince the West that the frontlines in Ukraine are collapsing, such that Ukraine should concede to all of Russia’s demands. The Kremlin likely intends to portray these limited cross-border attacks against small rural border villages in long-dormant areas of the international border as part of a broad new Russian offensive to reinforce a false narrative that Ukraine’s frontline is collapsing across the theater. Russian President Vladimir Putin stated on December 17 that Russia will achieve all of its war goals militarily if it cannot do so diplomatically, including the creation and expansion of a “buffer zone” in Ukraine.[8] Putin first proposed creating a “buffer zone” in Ukraine in June 2023 following limited Ukrainian cross-border raids into Belgorod Oblast.[9] The Kremlin has since invoked the concept of this buffer zone multiple times to signal broader territorial demands in northern Ukraine, including Sumy and Kharkiv oblasts, likely to set conditions to later demand that Ukraine cede some or all of this territory due to Russia’s alleged need for a buffer zone.[10] The Kremlin will likely seek to use these attacks in combination with existing narratives about the creation of a buffer zone in Ukraine to convince the West to push Ukraine to concede to Russia because Russia will inevitably seize these areas regardless.[11] ISW continues to assess that the frontlines in Ukraine are not in danger of rapid collapse and that a Russian victory is not inevitable.[12]
Counterindicators: This assessment will be invalidated, and Russian forces will be more likely to be conducting an actual new ground offensive operation in northern Ukraine if Russian forces begin a concerted BAI campaign targeting Ukraine’s tactical and operational rear to degrade Ukraine’s frontline logistics or if Russian forces redeploy or commit new forces to the Northern Grouping of Forces’ area of responsibility. Such redeployments very likely would require the Russian theater command to deprioritize the southern and eastern frontlines. Both of these counterindicators remain unobserved as of December 21.
Russian forces forcibly deported about 50 civilians from Sumy Oblast in violation of international law. Hrabovske Mayor Larysa Kremenza stated on December 20 that there had been about 50 civilians left in Hrabovske when Russian forces entered the settlement and that Russian forces forcibly deported these civilians to Russia.[25] Kremenza stated that there were no children among those forcibly deported, and Lykhovyi stated that most of these civilians are elderly and had previously refused to evacuate.[26] Ukrainian officials indicated that they are increasing evacuation measures in Sumy Oblast border areas.[27] Forced deportation refers to an occupying power deporting residents of an occupied area across de jure international borders and is illegal under the Fourth Geneva Convention.[28] Russia has conducted an extensive forced deportation campaign in areas of occupied Ukraine for various purposes, including to Russify Ukrainian citizens, provide labor to industries in Russia, and undermine Ukraine’s ability to reintegrate areas currently under occupation.[29] This campaign across all of occupied Ukraine intends to rob Ukraine of its multigenerational potential and damage Ukraine’s future claims to its own people.[30]
Russian forces have likely seized Siversk — a town with a pre-war population of less than 11,000 — after 41 months of fighting. Ukrainian military observer Kostyantyn Mashovets reported on December 21 that Russian forces completed the seizure of Siversk, advanced to heights west and northwest of Siversk, and reached the chalk quarry west of Siversk.[31] Mashovets reported that Russian forces also made tactical gains north of Svyato-Pokrovske and seized Fedorivka and Vasyukivka (all southwest of Siversk) since mid-November 2025.[32] The Kremlin claimed that Russian forces seized Siversk as of December 11, and Russian President Vladimir Putin and senior Russian defense officials have since been using the seizure of the town to promote the false narrative that Ukrainian lines are collapsing and that Russian forces are capable of immediately threatening Slovyansk.[33] The Russian efforts in the Siversk direction have been extremely lengthy, especially given that Siversk has an area of about 10 square kilometers with a pre-war population of about 11,000. Russian forces took 41 months to advance roughly 12 kilometers from Lysychansk (east of Siversk) to the western administrative boundary of Siversk.[34] Ukrainian resistance significantly delayed Russian efforts on the approaches to Siversk: ISW assesses that Russian forces seized Verkhnokamyanske (about four kilometers east of Siversk) as of October 9, 2024, Bilohorivka (about 10 kilometers northeast of Siversk) as of February 23, 2025, and Serebryanka (about four kilometers northeast of Siversk) as of August 16, 2025.[35] ISW first observed evidence that Russian forces entered Siversk’s town limits no later than November 18, indicating that Russian forces likely took 33 days to completely seize the town (with an area of three Central Parks) once entering it.[36] Russian forces must still advance the 30 kilometers from Siversk to Slovyansk and complete the seizure of Lyman before they can begin a direct assault on Slovyansk itself.[37] The Kremlin has been exaggerating the immediate implications of the seizure of Siversk in attempts to falsely portray Russian forces as imminently threatening the northern part of the Fortress Belt and making significant simultaneous advances across the theater, such that the frontline is imminently collapsing. Russian gains continue to be slow and grinding as they have been for the past two years.
US delegations continued separate meetings with Ukrainian and Russian delegations in Miami on December 21, as the Kremlin continues to reject making compromises to end the war. Ukrainian Defense Council Secretary Rustem Umerov reported that he and Chief of the Ukrainian General Staff Major General Andriy Hnatov conducted a third day of meetings with US negotiators in Miami on December 21.[38] Russian state media reported that the lead Russian negotiator and Russian Direct Investment Fund (RDIF) CEO Kirill Dmitriev held separate meetings with US Special Envoy to the Middle East Steve Witkoff and former Senior Advisor to the US President Jared Kushner on December 21.[39] Russian Presidential Aide Yuriy Ushakov stated on December 21 that he is “confident” that European and Ukrainian proposals “do not improve” the peace proposal or “enhance the chances of achieving long-term peace.”[40] Russian President Vladimir Putin and other Kremlin officials have repeatedly rejected the US-proposed 28-point peace plan or any plan requiring Russia to compromise on any of its original war aims.[41] Putin notably used his December 19 Direct Line televised press conference to outline his demands for a future peace settlement — the same demands with which he launched the full-scale invasion in February 2022.[42]
Key Takeaways
- Russian forces are conducting a new cognitive warfare campaign through limited cross-border attacks across a broad part of the previously dormant northern frontline in Sumy and Kharkiv oblasts.
- These two cross-border attacks likely intend to advance the Kremlin’s cognitive warfare campaign to convince the West that the frontlines in Ukraine are collapsing, such that Ukraine should concede to all of Russia’s demands.
- Russian forces have not set conditions to start a new offensive across the international border in northern Ukraine.
- Russian forces notably have not prepared the battlefield in northern Sumy or Kharkiv oblasts for a major ground offensive through intermediate-range strikes against Ukrainian logistics.
- The Russian tactics in the assault in Sotnytskyi Kozachok are not consistent with Russian assault tactics across the theater and suggest the attack was designed to be seen.
- Russian forces forcibly deported about 50 civilians from Sumy Oblast in violation of international law.
- Russian forces have likely seized Siversk — a town with a pre-war population of less than 11,000 — after 41 months of fighting.
- US delegations continued separate meetings with Ukrainian and Russian delegations in Miami on December 21 as the Kremlin continues to reject making compromises to end the war.
- Ukrainian forces recently advanced in the border area of Belgorod Oblast and near Pokrovsk. Russian forces recently advanced in the Slovyansk-Lyman direction, in the border areas of Sumy and Kharkiv oblasts, and near Borova and Siversk.