Germany will need at least 75,000 additional troops to fulfil its NATO commitments as the alliance adapts its defence planning to face what it sees as an increasingly hostile Russia, Spiegel magazine reported on Friday.

At their Vilnius summit last year, NATO leaders signed off on the first major defence plans since the end of the Cold War, detailing how the alliance would respond to a Russian attack.

The move signified a fundamental shift - NATO had seen no need to draw up such plans for decades, as it fought smaller wars in Afghanistan and Iraq, and felt certain post-Soviet Russia no longer posed an existential threat.

NATO and national military planners have been busy translating the plans into concrete requirements, identifying shortages of troops, weapons and other equipment needed to defend against a Russian attack that could, according to the German military's top brass, come as early as 2029.

The new NATO requirements mean that the Bundeswehr will need an extra 75,000 troops to fill additional allied corps, divisions and brigades needed to implement the defence plans, Spiegel said, citing confidential documents without giving further details.

The German defence ministry was not immediately available for comment.

At the moment, the Bundeswehr has some 180,000 soldiers, falling short of the target of around 200,000 troops, and 80,000 civilian employees. (Reporting by Sabine Siebold Editing by Miranda Murray)