Prime Minister David Cameron and President Nicolas Sarkozy insist their countries' sovereignty is not threatened. But critics suggest the idea of troops regularly serving under foreign command could cause problems.
Carriers will be retrofitted to service both countries' planes
David Cameron and Nicolas Sarkozy put pen to paper on two treaties in London. The agreements will see Britain and France jointly testing nuclear warheads, coordinating aircraft carriers so there is always a British or French vessel available for joint operations, and creating a combined expeditionary force training troops to deploy together.
France will also be allowed to use British A400M fuelling aircraft when there is spare capacity and there will be joint work on drones, mine counter-measures and satellite communications.
Both men were keen to reject claims the move will diminish British or French sovereignty in any way. David Cameron insisted:
Britain and France want to get closer and save money too
"This is not, as some have suggested, about weakening or pooling British or French sovereignty. This is not about a European army. This is not about sharing our nuclear deterrents. Let me say this plainly: Britain and France are, and will always remain, sovereign nations, able to deploy our armed forces independently and in our national interest when we choose to do so."
David Cameron‘s Defence Secretary Liam Fox has pointed out that it is not unusual for British troops to serve under foreign command - it happens often in NATO operations.
The prime minister also said that UK forces are deployed alongside those of its allies on a regular basis, saying that "the vast bulk of our military operations - Bosnia, Kosovo, Afghanistan, amongst others, have been conducted together with our allies."
He added that such operations were always about defending Britain's national interest, and that they were "about practical, hard-headed co-operation between sovereign countries."
France and Britain have disagreed, even fairly recently, on military intervention - for example, on the invasion of Iraq in 2003. So President Sarkozy and Prime Minister Cameron were sure to point out that a 'political agreement' would have to be reached for the joint taskforce to be deployed.
Sarkozy maintained, however, that France and Britain already cooperated on major military operations and would continue to do so.
"If you, my British friends, have to face a major crisis," said Sarkozy, "could you imagine France simply sitting there, its arms crossed, saying that it's none of our business?"
'Unprecedented And Historic'
Sarkozy did say, however, that the pacts demonstrated that Britain and France were especially close at the moment, and hailed the Anglo-French relationship: "This is an unprecedented decision and it shows a level of trust and confidence between our two nations that is unequalled in history."
France and Britain, historical enemies, have grown quite close
The French President, also aware that some analysts had described the pact as a signal of an overall weakening of combined British and French military power, was quick to dispel that notion.
"We consider that the security effort should not in any way be drawn down in an increasingly dangerous world, which is that in which we live."
The two leaders do both hope, however, that co-operation can lead to savings in costs. The UK has recently announced cuts in its defense budget as part of its austerity drive and wants greater pooling of resources with France to help it maintain its military might, while bringing down its expense.
Britain's Shadow Defense Secretary Jim Murphy welcomed the emphasis on greater co-operation in military matters, saying that deepening ties is 'essential' to modern defense policy among allies.
However, he warned that "Interdependence is different from dependence, and binding legal treaties pose some big questions for the government."
Murphy also said the UK could be entering "an era where we are reliant on our allies to fill in the gaps in the government's defense policy."
Maintaining Global Might
France sends its soldiers far and wide, but could stand to save money
France and Britain's defense budgets are among the largest in the world. Both countries punch above their weight militarily and do not want to surrender their strategic advantage in this area.
Alastair Cameron, European Security expert at the Royal United Services Institute in London, thinks that is in little danger of happening, despite austerity drives.
"One could clearly be tempted to say that, forced to recognize their diminished stature in the world, these two countries are trying to do more together to avoid being overtaken by others," he said.
But Cameron also said the two countries were such significant military contributors to global military operations that it would be hard to see much diminishment of their ambition to play a part on the global strategic scene.
"The military is facing a squeeze, of course," said Cameron, "but there is no doubt that their capacity, even under austerity measures, maintains an edge over a good number or other countries."
Author: Olly Barratt
Editor: Matt Hermann