Germany is raising the number of its troops for the first time since 1990, ending a quarter of a century of successive cuts in the army since the end of the Cold War.

The Bundeswehr is expected to increase in the next seven years by 14,300 soldiers, while 4,400 civilian officers will also be added to the service, Defence Minister Ursula von der Leyen said.

This boost in troop strength is "necessary given the current situation" of increasing tensions with Russia over the conflict in Ukraine, as well as several foreign missions undertaken by the army, she said.

Germany is preparing to join efforts to bolster NATO's presence on its eastern flank bordering Russia, in a bid to reassure east European alliance members rattled by Moscow's annexation of Crimea.

The Bundeswehr has also deployed troops to Mali as part of a UN mission to monitor a peace deal between the government and northern rebels in the west African country.

It has also joined an international coalition battling IS jihadists in Iraq and Syria.

German soldiers totalled 178,000 last December, hovering close to the cap of 185,000 imposed since 2011.

The army has seen a significant reduction in troop numbers since Germany's reunification and after the Cold War.

In 1990, the number of soldiers reached 585,000.

Berlin's latest announcement also appeared to be an answer to a repeated call by the United States for NATO members to stump up more in defence spending.

US President Barack Obama made the plea in April during his visit to Germany, where he also berated Europe for having "sometimes been complacent about its own defence".