Britain has approved the use of Storm Shadow missiles in response to Russia's deployment of North Korean troops in the war against Ukraine, AP said, citing a source who wished to remain anonymous.

"Ukraine's armed forces fired British cruise missiles at military targets inside Russia for the first time, a Western official familiar with the matter said, as the 1,000-day conflict enters a new phase. The UK approved the use of Storm Shadow missiles in response to Russia deploying North Korean troops in its war against Ukraine, a move the British government considered to be an escalation, according to the person, who spoke on condition of anonymity because of the sensitivity of the matter," according to the statement.

The issue of allowing the Ukrainian Armed Forces to use Storm Shadows on Russian territory dominated the Group of 20 leaders' summit in Brazil this week after U.S. President Joe Biden gave the go-ahead for Ukraine to launch long-range ATACMS missiles at Russian targets. But UK Prime Minister Keir Starmer has not publicly backed the move, despite long being seen as a supporter, leading to questions about whether his government would allow the UK's Storm Shadows to be used.

"Storm Shadow debris was found in Russia's Kursk region to the north of Ukraine and two missiles were intercepted over Yeysk, a Black Sea port in the southern Krasnodar region, according to the Telegram channel Rybar, which has connections to the army and more than 1.3 million subscribers. The information couldn't be independently verified," the AP said.

It comes a day after Russia's Defence Ministry said Ukraine had used Western-supplied ATACMS missiles to strike a military facility in Russia for the first time.