The offensive by Ukrainian forces that led to the seizure of part of Russia’s Kursk region was prepared with the involvement of US, British and Polish intelligence services, Russian intelligence has concluded, according to a report in the Izvestia newspaper.

Units of the Ukrainian army carried out the surprise raid on the territory of Russia on August 6.

This is the largest military invasion of Russian territory since World War II.

The operation, Kiev says, is aimed at creating a buffer zone and wearing down Russia’s war machine — phrasing that mirrors terms the Kremlin has occasionally used for what it has dubbed a “special military operation,” the Russia-Ukraine war that broke out at the end of February 2022.

“The operation of the Ukrainian armed forces in the Kursk region was prepared with the participation of US, UK and Polish intelligence services,” Izvestia summarized, citing Russian espionage.

“Participating units were trained in combat coordination at training centers in the UK and Germany,” he continues.

Russian intelligence assured the newspaper that it had “reliable information” about the claim, without disclosing from which sources or providing evidence.

The White House has argued that Washington did not know in advance that a Ukrainian attack on Kursk was being planned.

As Russian troops continue their slow advance into eastern Ukraine, where they are focusing their own operations, Kiev said yesterday that its forces had seized 1,263 square kilometers in Kursk, including 93 communities. The Reuters news agency notes that it is unable to independently verify these numbers.