Pilots of the Russian Warriors air force aerobatic squadron fly their Su-27s and fire flares during a demonstration flight at the Moscow International Air Show: Oleg Nikishin/Getty Images

Russia's air force has been ordered to prepare for a "time of war".

President Vladimir Putin has ordered a "snap check" of the country's armed forces, accoording to defense minister Sergey Shoigu. As well as checking whether agencies and troops are ready for battle, the same order will ensure that systems are ready to fight, according to state news agency TASS.

Those preparations have already begun, according to Russian ministers.

"In accordance with the decision by the Armed Forces Supreme Commander, a snap check of the Aerospace Forces began to evaluate readiness of the control agencies and troops to carry out combat training tasks," he said, according to TASS.

"Special attention should be paid to combat alert, deployment of air defense systems for a time of war and air groupings’ readiness to repel the aggression," Shoigu added.

The preparations come amid increasing concern about tensions between Russia and many of the world's largest superpowers. Donald Trump has both condemned Russia's military campaigns and been criticised for being too close to the country's leaders, and Russia itself is standing in an increasingly tense relationship with some Nato countries.

The country has been increasing movement of its military including the launch of the biggest Arctic military push since the fall of the Soviet Union, last month. It has also revealed plans to expand its military over 2017, including a huge boost in the number of tanks, armoured vehicles and aircraft controlled by the company.