The 11 most incredible weapon systems used by the Russian army

The United Kingdom is planning to send 800 troops to the Russian border as tensions between Moscow and the west continue to increase.

Defence Secretary Michael Fallon announced the news after NATO called on member states to contribute to its biggest military presence on Russian borders since the Cold War.

Relations between Vladmir Putin's Russia and the west have been frosty since Russia's annexation of Crimea in 2014 but have worsened in recent months over the role Russia has played in the Syrian civil war.

Putin's Russia has gone through a significant transformation since the president's re-election in 2012. It had the world's fourth-largest defence budget in 2015, at a cost of $66.4 billion (£46 billion).

For that, the state boasts 845,000 troops, 22,550 tanks, and 1,399 combat aircraft.

The army is being split into smaller, more dynamic brigades. The focus is on new technologies rather than brute manpower. (For instance, this Pantsir-S1 anti-aircraft system is basically a tank with a load of extra cannons sticking out of it.)

Here's a review of some of Russia's more menacing military machines.

Tomas Hirst contributed to this slideshow: