PARIS — UK Prime Minister David Cameron last week announced a plan with France to invest more than £1.5 billion (US $2.1 billion) to build a prototype combat drone, signaling a further step by the two European partners to stay in the military top tier on a bilateral basis.

"Today we have agreed to jointly invest £1.5 billion to develop the next generation of a combat air system," Cameron said at a March 3 joint press conference with French President François Hollande, at Amiens, northern France. The project would support jobs and expertise.

Hollande said, "There has been much progress, much common willingness, which has also been translated into programs" since the 2010 Lancaster House defense treaties.

The agreement was for a £1.54 billion project "to build a prototype of the next generation of unmanned aircraft," the British Ministry of Defence said.

France also agreed to consider an order for the MBDA Brimstone 2 guided missile to arm the Tiger attack helicopter, while Britain will weigh whether to fit the Aster Block 1 New Technology missile on its Type 45 destroyer, a joint statement said. That marked a "portfolio approach" of strengthening industrial links and operational requirements.

Britain will also provide a monthly strategic airlift to support French troops deployed in Africa, the British ministry said.

Work will start next year on full-scale development of an unmanned combat aerial system (UCAS), with operational  prototypes by 2025, the joint statement said. A technical review is due in 2020 and a versatile UCAS could be flying as the basis for full operational capability beyond 2030. The two countries will study future combat conditions, including how manned and unmanned aircraft might fly together.

"It’s moving ahead," said Jean-Pierre Maulny, deputy director of the think tank Institut des Relations Internationales et Stratégiques. There is continued support for an Anglo-French demonstrator, which is a project rather than a program. Other European countries may be wondering whether they will have a role.

"It is important to prepare for the future in the strategic domain of combat drones," said Eric Trappier, chairman of Dassault Aviation.

The future combat air system project is based on a £120 million feasibility study conducted by BAE Systems, Finmeccanica Airborne and Space Systems Division, and Rolls-Royce work on the British side, with Dassault, Safran’s Snecma and Thales on the French side.

The 2014 bilateral summit announced the feasibility study, equally funded by Britain and France.

Defense Ministers Jean-Yves Le Drian and Michael Fallon agreed to the cooperative projects at the Amiens meeting.

"Brimstone missile would be a significant option for the upgrade of their Tiger attack helicopters," Fallon said in a statement.

MBDA has studied fitting the Brimstone 2, a dual-mode laser and radar-guided weapon, on British Army Apache helicopters, in addition to arming strike fighters.

Britain and France also signed a statement of intent for a concept phase for a future cruise/anti-ship weapon to replace the French Scalp, Exocet and naval cruise missile, and the British Storm Shadow, Harpoon and Tomahawk weapons. Contracts could be signed by March of next year following agreement by the end of 2016 on the concept stage studies. Decisions are due in 2020 for the subsequent assessment phase.

The two governments agreed to commit in 2016 to a plan worth some €150 million (US $163.4) to develop and build unmanned underwater vehicles for maritime mine countermeasures. Last year, a Thales-led consortium including BAE Systems won a tender for a system design contract worth £17 million.

The Anglo-French 2010 Lancaster House defense treaty sought to boost bilateral cooperation on the operational and industrial front.

That cooperation at an operational level reached a new high when the British Ministry of Defence announced Feb. 24 that it was conducting an officer swap with the French Army not seen since World War I. A senior French officer is set to become deputy commander of the 1st (United Kingdom) Division, the British Army's light role adaptable force.

A British Army colonel will become deputy commander of the French equivalent , the EMF1 ( Etat-major de force). A separate move will see a French general join the senior ranks of the British military.

The meeting between Hollande and Cameron at Amiens marked a 100-year commemoration of the battle of the Somme during the World War I, when British and French troops led an allied attack on the German front line that left some 600,000 dead and wounded.

France and Britain separately built and flew UCAV technology demonstrators, respectively the Neuron and Taranis, with the former leading a European group comprising Greece, Italy, Spain, Sweden and Switzerland. Further Neuron flights are due this year, French procurement chief Laurent Collet-Billon said Feb. 10

Andrew Chuter contributed from London.

More In Air Warfare