There is a limit to how far Britain can rely on French military help, Arbuthnot said, citing the example of the Falkland Islands, over which it warred with Argentina in 1982.
Argentina has in recent months stepped up its rhetoric in staking its claim to “Las Malvinas”.
“Doing more with allies means that you have to decide to get rid of capability because you will be relying on your ally to provide that capability in times of need,” Arbuthnot said.
“How can we be sure, and this is an existential question, that that capability would be available even after a change of government in our allied country and in circumstances where that ally profoundly disagreed with our policy?”
Paris sees the issue differently. “The Falklands is not a good question. What if? You have hundreds of cases with no answers,” the French official said, adding the real question was whether a country could afford full military capability alone.
“If that’s the case, then there is no need for cooperation. If it’s not the case, then you may have to accept some risks, and choose a partner you’re ready to work with.”
(Additional reporting by John Irish; editing by Andrew Roche)