Europe on war-footing: Britain sends tanks, drones and 800 troops to Estonia as part of the biggest military build-up on Russia's borders since the Cold War after Putin completes nuclear drill for 40 million people

Britain is sending tanks, drones and 800 troops to Estonia as part of the biggest military build-up on Russia's borders since the Cold War - after the Kremlin completed a nuclear drill for 40 million people.

The soldiers will be sent to the Eastern European country and will be joined by forces from Denmark and France, according to Defence Secretary Michael Fallon.

The United States hopes for binding commitments from Europe to fill four battle groups of some 4,000 troops, part of NATO's response to Russia's 2014 annexation of Crimea and concern it could try a similar tactic in Europe's ex-Soviet states.

France, Denmark, Italy and other allies are expected to join the four battle groups led by the United States, Germany, Britain and Canada to go to Poland, Lithuania, Estonia and Latvia, with forces ranging from armoured infantry to drones.

Tensions are high between Russia and the West after an escalation in posturing between President Vladimir Putin and Western leaders.

Last week Putin sent an aircraft carrier on a bombing mission to Syria in a fleet that passed through the English Channel. In the past week, Britain has deployed RAF fighter jets to intercept Russian bombers nearing UK airspace twice in four days.

Yesterday, Russia unveiled chilling pictures of its largest ever nuclear missile - Satan 2 - which is capable of destroying an area the size of obliterating the UK. Earlier this month the Kremlin evacuated 40 million people in drills to prepare for nuclear war.

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