Vladimir Putin says Ukraine’s invasion of Russia’s Kursk region, which has caused 100,000 people to flee, is an attempt to halt Moscow’s offensive in eastern Ukraine.
Russian forces are still scrambling to respond to the surprise attack, which has seen a substantial amount of territory come under Ukrainian control.
The Russian president’s comments came as one of his governors accused Ukraine of chemical weapon use during the offensive – though it is unclear if he has provided any evidence.
War latest: Ukraine ‘now controls 1,000sq km of Russian territory’
Both Russia and Ukraine have accused one another and reported allegations of use of chemical weapons during the war.
The Ukrainian operation is taking place under tight secrecy, and its goals – especially whether Kyiv’s forces aim to hold territory or are staging hit-and-run raids – remain unclear.
Mr Putin said the Kursk offensive appeared to reflect Kyiv’s attempt to gain a better negotiating position in possible future talks to end the war.
“It’s obvious that the enemy will keep trying to destabilise the situation in the border zone to try to destabilise the domestic political situation in our country,” he added.
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The commander of the Ukrainian military, Colonel General Oleksandr Syrskyi, said Ukraine now controls around 1,000 square kilometres (386 square miles) of Russian territory in the Kursk region.
Earlier, acting Kursk governor Alexei Smirnov reported to Mr Putin that Ukrainian forces had pushed 12 kilometres (7.5 miles) into the Kursk region across a 40-kilometre (25-mile) front and currently control 28 Russian settlements.
He said 12 civilians have been killed and 121 others, including 10 children, have been wounded in the operation. About 121,000 people have been evacuated or left the areas affected by fighting on their own, he said.
Ukrainian President Volodymyr Zelenskyy issued his first comments on the invasion of Kursk over the weekend, saying that Russia deserved a “fair” response after it launched nearly 2,000 cross-border strikes at Ukraine’s Sumy region over the summer.
Moscow ‘severely embarrassed’ by invasion
Speaking as the Kursk operation approaches a week, Matthew Savill, military sciences director at the Royal United Services Institute, said Russia has been “severely embarrassed”.
“The loss of territory and evacuation of civilians will play poorly back in Russia as evidence they ‘can’t defend themselves’,” he added.
However, Mr Savill cautioned that sustaining a force inside Russia and defending against counter attacks will be “hard” due to Ukraine’s “limited reserves”.
He said: “While the Ukrainians have reversed the public narrative about being on the defensive, it seems unlikely they would want to sustain a large incursion for months; they will have a decision to make about the best time to trade in the ground they have captured, and to what end.”