NATO has called on Germany’s prospective new coalition government to back the alliance’s nuclear deterrence strategy.

- Our aim is a world free of nuclear weapons. But as long as others have them, NATO must have them too - Secretary General Jens Stoltenberg said in Berlin on Friday.

His remarks came after claims that prospective coalition partners, the Social Democrats, Greens, and Free Democrats, may soon agree on a foreign policy blueprint contradicting NATO’s nuclear deterrence.

Addressing a group of foreign policy experts, politicians, and journalists at the German Atlantic Association, Stoltenberg said Germany has a special responsibility to keep NATO strong.

- And I count on Germany to remain committed to NATO’s nuclear sharing. It is our ultimate security guarantee - he added.

He warned that Russia has invested significantly in recent years in military capabilities, including new, advanced nuclear weapons.

Media reports earlier speculated that the new German government may take steps towards the withdrawal of US nuclear bombs, which are stationed in the country as part of NATO arrangements.

Stoltenberg said nuclear weapons stationed in Europe provide allies an effective nuclear umbrella.

- And they are an important signal of Allied unity against any nuclear-armed adversary. So NATO’s nuclear sharing arrangements are of particular importance for Europe - he said.

As many as 20 US B61 nuclear bombs are said to be stored at the Buechel Air Base in southwestern Germany, as part of NATO's nuclear deterrence doctrine.

Stoltenberg said that if Germany’s new government withdraws from NATO’s nuclear sharing arrangement, then the alliance would seek other alternatives and deploy these weapons in another country in Eastern Europe.

- As Germany, you can of course decide whether there will be nuclear weapons in your country. But, the alternative is that we easily end up with nuclear weapons in other countries in Europe, also to the east of Germany - he said.

The Greens have long argued that the country should be free from nuclear weapons, and it wants Germany to join the UN’s nuclear weapons ban treaty. Senior members of the Social Democrats also publicly opposed deployment of US nuclear weapons on German territory.

The Free Democrats, meanwhile, are backing nuclear disarmament initiatives, but insist that any decision on the withdrawal of US nuclear weapons from Germany should be coordinated with NATO allies.