This timeline of the Russo-Ukrainian war covers the period from 1 September to 30 November 2023 during the 2023 Ukrainian counteroffensive.
September 2023 1 September In Russia, three drones were intercepted by air defenses over Pskov and Belgorod Oblasts, while another reportedly hit a factory that manufactured electronic components for rockets in Lyubertsy, Moscow Oblast, forcing the closure of airports in the area. At least two buildings were reportedly damaged in another drone attack in Kurchatov, Kursk Oblast.
One person was killed by Russian shelling in Kherson.
The British weapons firm BAE Systems opened a branch in Ukraine as part of preparations to produce light artillery there.
Two container ships left Odesa through the temporary corridor introduced by Ukraine in the Black Sea.
The Ukrainian National Agency for Corruption Prevention (NACP) included PepsiCo and Mars, Incorporated to its list of international sponsors of the Russian war effort in Ukraine for continuing to operate in Russia.
Satellite images revealed that Russia had withdrawn air defences, artillery and tanks from the Kuril Islands as part of a possible redeployment to Ukraine.
The first Ukrainian crewmen completed their training on M1A1 Abrams tanks in the United States in anticipation of their delivery to Ukraine. However, their training was extended upon request by the Ukrainian government.
2 September Russia claimed to have destroyed three naval drones attempting to attack the Crimean Bridge, while the governor of Belgorod Oblast claimed that Ukrainian shelling killed one person in Urazovo.
The Ukrainian military claimed to have breached the first line of Russian defenses in the Zaporizhzhia front and were now pushing towards the succeeding defense line.
Four people, including a police officer, were killed by Russian attacks in Donetsk, Kherson and Sumy Oblasts.
The United States pledged depleted uranium armor-piercing rounds that can be fired from M1A1 Abrams tanks it was sending to Ukraine as part of a new military aid package valued at $240-$375 million.
A spokesperson for the Ukrainian Air Force said that the US would supply Ukraine with AMRAAM missiles, with Raytheon signing a contract to supply them to Ukraine valued at $192 million.
3 September
Russia launched an overnight drone attack on the port of Reni, injuring two people. The Ukrainian Air force claimed to have shot down 23 of 25 drones launched. Two people were killed in separate attacks in Donetsk and Kherson Oblast.
Ukraine claimed to have destroyed a Russian KS-701 patrol boat using a Bayraktar TB2 drone in the Black Sea, killing six and wounding two. In a separate attack in Luhansk Oblast, a Russian TOS-1A Solntsepyok heavy flamethrower system was reportedly destroyed by a drone, killing its crew.
Ukraine president Volodymyr Zelenskyy announced the dismissal of his Defence Minister Oleksii Reznikov and his replacement by Rustem Umierov, the manager of the State Property Fund of Ukraine and a negotiator in talks with Russia throughout the war. Zelenskyy said he had based his decision on finding "new approaches" for the ministry, which had also been caught up in several corruption scandals in recent weeks. Umierov's appointment was confirmed by the Verkhovna Rada on 6 September.
In Russia, Roman Starovoit, governor of Kursk Oblast, claimed that a Ukrainian drone was shot down over Kurchatov, with falling debris setting fire to a "non-residential building".
President Zelenskyy said France had agreed to help train Ukrainian pilots on the use of F-16 fighter jets.
4 September
Russia claimed to have shot down two drones over the Black Sea and in Kursk Oblast and destroyed four Ukrainian landing boats heading towards Crimea. It also launched an overnight drone attack on Ukraine's Danube ports, damaging several buildings but causing no injuries. Ukraine claimed to have shot down 23 of 32 drones launched, with Romania saying drone parts fell on its territory. NATO said it did not believe that the spillover constituted a deliberate attack by Russia. In response, the Romanian government introduced additional security measures on the border settlements of Plauru and Ceatalchioi. One person was killed by shelling in Zaporizhzhia Oblast.
The Ukrainian Defence Ministry said its forces had retaken three square kilometers of territory around Bakhmut in the past week.
President Zelenskyy made another visit to Ukrainian positions in the Donetsk and Zaporizhzhia fronts.
A court in Russian-occupied Donetsk Oblast sentenced two Ukrainian soldiers to more than 20 years' imprisonment for alleged war crimes during the Siege of Mariupol.
Russian media reported that T-14 Armata tanks were withdrawn from service in Ukraine after being deployed in indirect fire roles to test them in "real combat conditions".
Belgium pledged eight RIM-7 Sea Sparrow missiles to Ukraine.
5 September Russia claimed to have shot down four drones over Tver, Kaluga, Moscow, and Bryansk Oblasts.
A Ukrainian Challenger 2 was destroyed near Robotyne, the first time a tank of that model was destroyed by a belligerent in action.
Yury Afanasyevsky, head of the customs office of the Russian-installed Luhansk People's Republic, was reportedly injured in a bomb attack at his home.
Cuba announced the discovery of a human trafficking network that recruited its nationals to fight in Ukraine under Russian military forces, denouncing it as an act of "mercenarism", and arrested 17 people.
Germany delivered a military aid package to Ukraine that included 188 Mercedes-Benz Zetros off-road trucks, four border protection vehicles, a Beaver bridge-laying tank, 20,000 pairs of safety glasses, and ammunition for Flakpanzer Gepard self-propelled anti-aircraft guns.
6 September
A missile struck the central market of Kostiantynivka, Donetsk Oblast, killing at least 17 people including a child, and injuring 33 others.
A Russian drone attacked the port of Izmail, killing one person.
President Zelenskyy announced the transfer of Pavlo Kyrylenko from his position as governor of Donetsk Oblast to become head of the Antimonopoly Committee of Ukraine.
US Secretary of State Antony Blinken visited Kyiv and announced another aid package to Ukraine valued at more than $1 billion, which included about $665 million worth of security assistance and $175 million in military hardware that included HIMARS artillery, Javelin antitank weapons, Abrams tanks, and depleted uranium ammunition. France also delivered 150 Delair drones to Ukraine.
Ukraine claimed that a HIMARS strike on the village of Myronivs'kyi in occupied Donetsk Oblast destroyed a stockpile of Vikhr missiles used by Russian Ka-52 attack helicopters.
7 September Another wave of drone attacks was reported across Russia. In Rostov-on-Don, one person was injured and three buildings were damaged in a reported strike by two drones at the headquarters of the Southern Military District. Another drone was shot down over Moscow Oblast. A drone fell on a military facility in Volgograd Oblast, while another drone caused a fire at an industrial facility in Bryansk.
More than 270,000 tonnes of grain were reportedly destroyed by a Russian drone attack in the Danube river ports. Ukraine claimed to have shot down 14 drones. Two people were killed by Russian shelling in Kherson and Zaporizhzhia Oblasts.
Ukrainian border guards reclaimed the frontier settlements of Stroivka and Topoli, both of which lay in a recently de-mined "gray zone" between Ukrainian and Russian positions in Kharkiv Oblast.
The British Royal Air Force began surveillance flights over the Black Sea to protect grain shipments from Russian attacks.
The Pentagon pledged another military aid package to Ukraine worth $600 million which included air defense equipment, additional ammunition for HIMARS systems, 105 mm artillery rounds, electronic warfare, mine-clearing equipment, demolition munitions, training, and maintenance support.
A court in Abakan, Russia, sentenced journalist Mikhail Afanasyev to more than 5 years in prison and a 2.5-year ban on him practicing his profession for reporting on antiwar sentiment in Khakassia.
UNESCO approved a request by Ukraine to place 20 landmarks to the international list of cultural heritage sites under enhanced protection to deter military attacks. The sites included the Kyiv Pechersk Lavra, the Historic Centre of Lviv, Taras Hill in Cherkasy Oblast, the Derzhprom building in Kharkiv, and the wooden churches of the Carpathian regions.
The US and the UK sanctioned 11 members of the Russian cybercrime group Trickbot for launching ransomware attacks on foreign entities and targeting critics of the invasion of Ukraine.
8 September
Russia launched a wave of missile attacks on cities across Ukraine, including in Zaporizhzhia and Sumy. In Kryvyi Rih, a police officer was killed and 74 others were injured in a missile strike on a police station, while 69 structures were damaged. Three people were killed by Russian shelling in Kherson Oblast.
The Ukrainian military claimed to have retaken more than half of the village of Klishchiivka, south of Bakhmut, while noting that Russia had assembled a strike force near the village of Novohryhorivka in Luhansk Oblast in preparation for an offensive towards Lyman.
Russia began holding local sham elections in occupied areas of Ukraine until 10 September. During polling, the exiled mayor of Melitopol claimed that the regional headquarters of the United Russia party was destroyed in an incendiary incident, producing casualties on Russian authorities.
The Ukrainian government announced the repatriation of nine children deported to Russia, one of whom was imprisoned for allegedly blowing up a bridge.
Lithuania delivered 1.5 million rounds of ammunition to Ukraine.
9 September One person was killed by Russian shelling in Kherson Oblast. A Canadian volunteer for the non-government organisation (NGO) Road to Relief and the organization's Spanish director were killed after their vehicle came under Russian artillery fire near Chasiv Yar. Two other foreign volunteers were wounded.
A Russian soldier guarding polling stations during the Russian-organized local elections was reportedly killed in a car bombing in Nova Kakhovka by Ukrainian partisans, who also hacked into Russian television broadcasts in Crimea and called for a boycott of the elections.
The Russian-installed head of Crimea Sergey Aksyonov claimed three drones were shot down over the peninsula.
The G20 issued a joint declaration at the end of its annual meeting in New Delhi that produced a milder stance on the invasion of Ukraine compared with the previous summit held in Bali, avoiding mention of Russian involvement in the conflict.
Major General Kyrylo Budanov, chief of Ukrainian military intelligence, said that their counteroffensive would go on into winter.
10 September Russia launched an overnight drone attack on Kyiv, injuring one person in the Podil neighborhood. Ukraine claimed to have shot down more than 24 drones launched. One person was killed in a separate attack in Zaporizhzhia Oblast.
Eight Ukrainian drones were reportedly shot down by Russian air defenses near Crimea, while Russia also claimed to have destroyed three Ukrainian military transport vessels north-east of Snake Island.
South Korean president Yoon Suk-yeol announced the establishment of a $2.3 billion aid package to Ukraine for humanitarian and postwar recovery concerns.
11 September The Ukrainian defence ministry claimed its forces had retaken parts of the village of Opytne, three kilometers northwest of Donetsk, as well as 4.8 square kilometers of territory in the southern front over the past week.