Vladimir Putin has issued an ominous warning that whether Russia might strike British military sites is a "military secret", following the UK's decision to give Ukraine blueprints for the Scalp missile, a variant of the Storm Shadow that can strike deeper into Russian territory. The remarks escalate tensions between Moscow and London after Russia had already accused the UK of "playing with fire" over the move, with Prime Minister Andy Burnham rejecting the criticism by pointing to Russia's invasion of Ukraine as the true cause of the conflict.

Russian foreign minister Sergei Lavrov said Moscow had the right to treat British involvement in supplying missile technology as "participation in the war", while Putin insisted "any military facilities in Ukraine are our legitimate target, British or otherwise". Burnham, on his first foreign trip as prime minister, marked Ukraine's 35th independence anniversary in Kyiv by pledging continued support "despite Russia's outrageous threats". The row comes as defence secretary John Healey faces pressure to raise UK defence spending to 3% of GDP and has announced new measures, including a nationwide alert targeting the "A7 network", to disrupt Kremlin-linked sanctions evasion.