Ukraine has reportedly fired UK-supplied Storm Shadow cruise missiles at targets inside Russia for the first time.

Quoting a Western official familiar with the matter, Bloomberg News reported on Wednesday that Britain approved the use of Storm Shadow missiles in response to Russia deploying North Korean troops in its war against Ukraine. 

The official reportedly said the British government considered the move by Moscow to be an escalation. 

Quoting a Russian military blogger, the British daily the Telegraph reported the same day that fragments of a Storm Shadow missile were found in a village in Russia’s Kursk region, where North Korean troops have been deployed.

The strike came a day after Ukraine reportedly fired six missiles using the U.S.-made Army Tactical Missile System for the first time to strike a military facility in Russia after U.S. President Joe Biden approved Kyiv’s limited use of the weapons to hit targets inside Russia.