Kremlin aide says the West helped Ukraine attack Russia

The lightning incursion, the biggest into Russia by a foreign power since World War Two, unfurled on Aug. 6 when thousands of Ukrainian troops crossed Russia's western border in a major embarrassment for Putin's military.

The United States and Western powers, eager to avoid direct military confrontation with Russia, said Ukraine had not given advance notice and that Washington was not involved, though weaponry provided by Britain and the U.S. is reported to have been used on Russian soil.

Influential veteran Kremlin hawk Nikolai Patrushev dismissed the Western assertions in an interview with the Izvestia newspaper.

"The operation in the Kursk region was also planned with the participation of NATO and Western special services," he was quoted as saying, without offering evidence.

"Without their participation and direct support, Kyiv would not have ventured into Russian territory."

The remarks implied that Ukraine's first acknowledged foray into sovereign Russian territory since Moscow sent its forces into Ukraine in 2022 carried a high risk of escalation.

KREMLIN SAYS UKRAINE WILL PAY FOR US INVOLVEMENT

"Washington's efforts have created all the prerequisites for Ukraine to lose its sovereignty and lose part of its territories," Patrushev said.

Ukraine said on Thursday that it had installed a military commandant in the area it controlled, even as Russia intensified its offensives in Ukraine's east.

While the Ukrainian attack has revealed weaknesses in Russian defences and changed the public narrative of the conflict, Russian officials said Ukraine's "terrorist invasion" would not change the course of the war.

Russia has been advancing for most of the year in the key eastern sector of the 1,000-km (620-mile) front and has vast numerical superiority. It controls 18% of Ukraine.

After more than 10 days of fighting, Ukraine holds at least 450 sq km (175 sq miles) of territory, or less than 0.003% of Russia. But for Putin, the incursion crosses another red line.

He said on Monday that Russia would deliver a "worthy response" beyond ejecting Ukraine's forces.

One Russian source told Reuters the incursion could embolden hardliners in Moscow who advocate a bigger war, but Putin's choice may not be easy.

He has sought to portray Europe's biggest war in seven decades both as a limited "special military operation" that need not upset daily Russian life and as a historic fight with a West that scorns Moscow's interests and seeks to dismember Russia.

TRYING TO AVOID NATO-RUSSIA CONFLICT

The U.S., which rejects such allegations but says it cannot allow Russia to seize part of a sovereign neighbour, so far deems the surprise incursion a protective movethat justifies the use of U.S. weaponry, officials in Washington said.

But they also expressed worries about complications as Ukrainian troops push further into enemy territory.

One U.S. official, speaking on condition of anonymity, said that if Ukraine started taking Russian villages and other non-military targets using U.S. weapons and vehicles, it could be seen as stretching the limits Washington has imposed, precisely to avoid any perception of a direct NATO-Russia conflict.

Britain said on Thursday that weaponry it had given to Ukraine could be used inside Russia to help Kyiv defend itself, and a British source said British Challenger 2 tanks were thought to have been used on Russian territory.

Russia's defence ministry has published footage that it said showed a Russian drone destroying a U.S.-made Stryker armoured combat vehicle in the Kursk region.

Separately, the defence minister of Belarus, which Russia used as one launch point for the conflict in 2022, said there was a high probability of an armed provocation from Ukraine and that the situation at their common frontier was "tense".

(Reporting by Guy Faulconbridge in Moscow and Olzhas Auyezov in Almaty; Editing by Tom Hogue and Kevin Liffey)