In a move that would have been unthinkable two centuries ago, a French brigadier-general will be made deputy commander of a British Army division.
The unprecedented appointment comes amid an effort to strengthen military ties across the Channel.
A treaty signed in 2010 by the UK and France promised closer co-operation between the British military and its French counterparts.
“The French brigadier general will be in command of British soldiers and if the general goes on holiday, then he will be in charge."
This will be the first time a French officer has been tasked to command at such a senior level in the British Army.
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As part of the exchange, British Colonel Nick Nottingham will take up a similar role in the French Army.
An Army spokeswoman said: “These and the 17-plus posts that are exchanged between the French and British armies demonstrate the long-term commitment to providing security at home and abroad.”
The French brigadier general, who has not yet been announced, will be made Deputy Commander of 1st (UK) Division from April.
Brigadier General Mike Tarsa was given command of the 3rd (UK) Division. Speaking at the time, Brigadier Tarsa said it was an “honour” to be appointed the task.
Generals have justified the decision to work closer with neighbours as Britain is unlikely to go to war on its own in the future.
A British military mentor training troops in Mali, where the French are leading operations against Boko Haram
Any large military operations have in recent history been as part of coalitions of allies, as the Iraq and Afghanistan campaigns show.
One senior officer said: “Whenever you deal with the Americans, because of their size, they are always the elephant and we are always the mouse. No matter how courteous they are, it’s very clear who is in charge.
“We’ve found working with the French, that they are a similar size to us, we’ve both had empires and we just seem to understand each other. It turns out the language barrier isn’t as important as we thought. It’s all about distance and scale.”
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