France and Germany have agreed a compromise on NATO’s future as a nuclear-armed alliance, officials said Friday, as the bloc met in Lisbon to outline its new long-term strategy.

Germany had wanted NATO’s new “strategic concept” to commit the allies to a Europe free of nuclear weapons, while its neighbour France remains wedded to its independent deterrent as the bedrock of its security.

But diplomatic sources at the summit said they had agreed a “neutral” form of words that satisfies both, by expressing hope for future disarmament while insisting that NATO would keep nuclear weapons as long as others do.

“An accord has been reached between France and Germany on the points under discussion,” a French official said, speaking on condition of anonymity while the 28 NATO leaders met in closed-door session.

The summit will see the allies agree to set up a continent-wide missile defence shield but, while some in Germany would like to see this replace deterrence, France believes nuclear weapons must remain as a last resort.