Russia has warned that the use of US long-range missiles by Ukraine will lead to “an appropriate and tangible” response.

A statement issued by the foreign ministry said that such an attack inside Russian territory “would represent the direct involvement of the United States and its satellites in hostilities against Russia”

The BBC reports: President Joe Biden approved the use of the missiles on targets in Russia in a major change of US policy – two months before he is due to leave the White House.

It is not clear if his successor, President-elect Donald Trump, was consulted or whether he will stick by the decision, having promised to end the Russia-Ukraine war.

Ukraine has had US ATACMS (Army Tactical Missile System) with a range of 300km (190 miles) – as well as French and British Storm Shadow missiles of a similar range – but the Western allies had barred Kyiv from hitting Russia with them.

Biden’s decision to lift that condition is a significant moment in the war, which marks its 1,000th day on Tuesday.

On Tuesday Russian President Vladimir Putin announced critical updates to Russia’s nuclear doctrine, signaling a potential nuclear response to conventional missile strikes.

He emphasized that any attack on Russia, even by non-nuclear nations supported by nuclear-armed states, would be considered a collective assault on the Russian Federation.

The new document lists ten threats that require counteraction through deterrence.