VLADIMIR Putin has ordered his army and air force to prepare for a 'time of war' during a check of the country's armed forces.

Russia's defence ministry confirmed the measures during a "snap check" that included its massive S-300 and S-400 missile defence systems.

10 Vladimir Putin has put his troops on standby amid massive NATO exercises in eastern Europe Credit: Getty Images

10 US soldiers organise the delivery of tanks to Lithuania where NATO exercises are taking place Credit: Reuters

10 A soldier unloads a M1 Abrams tank to be tested across Latvia Credit: Reuters

10 German Defense Minister Ursula von der Leyen, right, and Lithuania's Presidend Dalia Grybauskaite speaks with a soldier wearing camouflage Credit: AP:Associated Press

10 Dutch soldiers take part in a parade while the NATO banner hangs above them Credit: EPA

Minister Sergey Shoigu said: "As part of a snap combat readiness check of the Aerospace Force, units of the Aerospace Force’s antiaircraft missile and radio-technical troops have arrived at the designated areas," TASS reported.

"Upon their arrival at the new positions, the crews of radar stations, S-300 and S-400 antiaircraft missile systems carried out maintenance work on their military hardware and went on combat alert.

"As the combat crews of radar stations and antiaircraft missile systems detect unidentified aerial targets, air defense patrol fighter jets will be scrambled to classify them or notionally destroy them."

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The warning is a likely a response to the massive NATO operations currently underway in eastern Europe.

Germany and NATO this week underscored their commitment to beefing up the defence of eastern Europe's border with Russia as the first of four new batallions under the North Atlantic alliance's banner arrived in Lithuania.

In moves agreed last year under former President Barack Obama, NATO is expanding its presence in the region to levels unprecedented since the Cold War, prompted by Russia's annexation of Crimea and accusations that it is supporting a separatist conflict in eastern Ukraine.

The German-led battle group of 1,000 troops in Lithuania will be joined this year by a U.S-led deployment in Poland, British-led troops in Estonia and Canadian-led troops in Latvia.

10 Lithuanian snipers take part in training exercises in Eastern Europe Credit: EPA

10 Local forces were supported by US and other NATO member troops Credit: AP:Associated Press

10 A German soldier salutes during the massive military exercises Credit: AP:Associated Press

10 Rows of tanks are deployed along the border with Russia which are contributing to deteriorating relations between Putin and the West Credit: Reuters

They will add to smaller rotating contingents of U.S troops.

Doubts about the US commitment to NATO have surfaced since the election of President Donald Trump, who has described NATO allies as "very unfair" for not contributing more financially to the alliance.

German Defence Minister Ursula von der Leyen said Europe realised it needed to strengthen defence cooperation and was doing more to solve its own problems.

She also said U.S. Secretary of Defence James Mattis reassured her about Washington's commitment to NATO in a recent telephone call.

"After what we discussed, I have no doubt about his deep conviction in the importance of NATO and the commitment of the Americans within NATO to what we have agreed," she said at a welcoming ceremony at Lithuania's Rukla military base, 62 miles from the Russian border.

10 The drills are part of a massive NATO exercise ordered by former US president Barack Obama Credit: Reuters

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