Britain and France signed defense agreements on Tuesday that promised cooperation far beyond anything achieved previously in 60 years of NATO cooperation, including the creation of a joint expeditionary force, shared use of aircraft carriers and combined efforts to improve the safety and effectiveness of their nuclear weapons.
The agreements signed in London by Prime Minister David Cameron of Britain and President Nicolas Sarkozy of France were a landmark of another kind for two nations that spent centuries confronting each other on the battlefields of Europe. While neither leader mentioned Agincourt, Trafalgar or Waterloo, or French victories that included the Norman Conquest in 1066, both stirred a brief whiff of the troubled history of Anglo-French relations into the mood of general bonhomie.
The agreements envisaged a new combined force available for deployment at times of international crisis that is expected to involve about 5,000 service members from each nation, with land, sea and air components, and rotating French and British commanders. The pacts also foresee each nation alternating in putting a single aircraft carrier to sea, with the vessels operating as bases for French, British and American aircraft in times of need.
The nuclear agreement was in some ways the most surprising, since it committed the two nations to sharing some of their most carefully kept secrets. Although the two leaders emphasized that France’s “force de frappe” and Britain’s similar, submarine-based ballistic missile force would remain separate and under the sole control of each government, they agreed to establish joint research centers, one in France and one in Britain, to further research on their stockpiles of nuclear warheads.
The cooperation pact was set to last 50 years and could transform the way the countries project force, fight wars and compete for defense contracts with the United States. One goal appeared to be to give the two militaries greater buying power to support the struggling European defense industry.
Mr. Cameron, who has navigated deep hostilities to European integration and deep skepticism toward France in his Conservative Party, emphasized the budgetary benefits, saying the agreements would contribute savings of “millions of pounds” to Britain’s plan to make deep cuts in its $60 billion defense budget.
Previous efforts at military cooperation between the countries have more often faltered than succeeded. In the late 1990s, Tony Blair, then Britain’s prime minister, and Jacques Chirac, then France’s president, promised deeper defense cooperation, but the understanding was undone by differences over the Iraq war. In both countries, there are significant political forces arrayed against anything that smacks of too close a military partnership with the age-old foe.
But after the Cameron government took office in May and began pushing for deep defense savings, it discovered a willing partner in Mr. Sarkozy. Britain and France have the biggest defense budgets in Europe, together accounting for more than half of all military spending in the 27-nation European Union. Both governments took care to say that their new cooperation was not intended to isolate Germany.
The nuclear agreement, carrying faint echoes of Britain’s shared role with the United States in the Manhattan Project, which developed the first atomic bomb, will have the two governments setting up two joint research centers, one in France and the other in Britain.
The two countries also agreed on a shared program on spare parts, maintenance and training for the crews of the Airbus A400M military transport aircraft, a costly, overbudget project intended to challenge American domination of the market for heavy-lift transports. They promised to work together on a new generation of remotely piloted surveillance aircraft.
Also on the list are shared projects to develop technologies for future nuclear submarines and military satellites, as well as countermeasures for mines and other antisubmarine weapons.
The high notes struck by the leaders at their news conference were striking.
“Today we open a new chapter in a long history of cooperation on defense and security between Britain and France,” Mr. Cameron said. Mr. Sarkozy said the agreements showed “a level of trust and confidence between our two nations which is unequalled in history.”
For all that, the shadows of Nelson and Napoleon, of Henry V and Joan of Arc, seemed to hang over the occasion, with both leaders feeling the need to gesture, at least obliquely, to the less generous attitudes that are common among some of their compatriots.
“I would like to say, contrary to what might otherwise seem to be the case, that the clocks in France and Britain strike the same hours, precisely,” Mr. Sarkozy said.
Mr. Cameron said: “It is about defending our national interest. It is about practical, hard-headed cooperation between two sovereign countries.”
One concern about the new agreements that has attracted criticism among British defense experts centers on the shared use of aircraft carriers.
With both countries planning to have only one “flattop” in their fleets, having them configured for each others’ aircraft has been described by the two governments as extending their ability to deploy air power, as well saving large sums. Last month, Britain decided to have its future carrier, due for deployment in 2020, redesigned with the catapult mechanism and arresting gear necessary to accommodate French and American aircraft.
But British critics have said military operations that require carrier-borne aircraft could be compromised if Britain has to rely on France’s allowing its carrier to be used. The example often cited is the 1982 Falklands war, when France opposed Britain’s reconquest of the Falkland Islands in the South Atlantic, and Argentina used French-made missiles to sink British ships.
Mr. Sarkozy described the criticism as outdated. “Can you imagine France sitting in our armed chairs and saying, ‘It is none of our business’ ?” he said.
Likewise, Mr. Cameron rejected suggestions that Britain would undermine its close military relationship with Washington. Mr. Cameron said the Obama administration would welcome the new plans. “They’d like us to have the biggest bang for our buck that we possibly can,” he said.
In France, Marine Le Pen, the vice president of the National Front, a far-right party, called Mr. Sarkozy the “gravedigger of General de Gaulle’s policy of independence.” She went on: “It is clear that the objective of this accord is to shift our defense to Anglo-Saxon control, and obviously everyone will understand that behind Great Britain there is, of course, the American big brother.”
In London, Mr. Cameron was chided by right-wing tabloids for trusting the French with Britain’s security, but his plans received a generally warm reception in Parliament. James Arbuthnot, a former Conservative minister who is the chairman of the House of Commons defense committee, told Mr. Cameron on Monday that he had “forgiven the French for taking off the head of my great-great-great-great grandfather at Trafalgar,” a reference to a captain who died in the great naval battle in 1805. Mr. Cameron said that was just as well, since Mr. Arbuthnot was invited to lunch with Mr. Sarkozy on Tuesday. “It might have been a little bit frosty,” he said.