BRUSSELS — European Union member states need to greatly expand cooperation Gen. Pierre de Villiers, the French chief of  the Defense Staff, said "further and deeper" cooperation at EU member state level is vital to meet "unprecedented" defense and security threats to Europe, said Gen. Pierre de Villiers, the French France's chief of the Defense Staff.

Future cooperation, he argued, might include sharing the costs of "employment and support," together with design, development and industrialization costs. Pooling or sharing in the field of operations, as well individual or collective training, are additional examples, of increased collaboration, he said.

"I am also thinking of cooperation on projects linked to in-flight refueling," said Gen. de Villiers said, who has been in his post since February of 2014. HeDe Villiers made his comments to the EDA's in-house journal, European Defence Matters, the in-house journal of the EU's European Defence Agency (EDA).

His remarks come in the wake of followed a damning new European Defence Agency (EDA) report published in March about a "worrying" the decline in defense expenditure by EU member states. The Brussels-based EDA says defense spending has been "declining steadily," and that, from 2006 to 2013, it fell falling by more than €32 billion (US $35.7 billion), or about 15 percent, from 2006 to 2013.

The EDA, an EU agency, said that between 2012 and 2013, collaborative equipment procurement expenditure decreased by 20.7 percent to €4.75 billion, its lowest level since 2006.€4.75bn

Seizing on current defense spending trends, Gen. de Villiers said: "Budgetary difficulties make it necessary to find new solutions in order to fill the gaps in budgetary programming."

France has been engaged in has been able to put its military resources to good use through actions in Afghanistan, Libya, Mali and against the Islamic State militant group, and in recently times has become a key European partner for the US military.

French armed forces have a reported strength of 215,019 regular personnel, but Gen. de Villiers, a former head of the French prime minister's military staff, said "increasing levels of threats very close to Europe's borders challenge our common capacity to cope with them."

This "serious and quite unprecedented" challenge requires , he supports increased cooperation among EU member states, he said.

De Villiers, France's top military officer, said, "We have to find pragmatic solutions which enable us to meet operational requirements at the lowest possible cost," De Villiers, France's top military officer, said. "The starting point of efficient cooperation is sharing a common vision, but I can see advantages in conducting programs in cooperation with partners."

One example of existing cooperation, he said, is the European Satellite Communication Procurement Cell, also known as the EU SATCOM Market.

Closer cooperation, he said, is possible in almost every domain "except some 'niche capabilities' linked to the heart of our operational or technological sovereignty."

"Cooperation has to be seriously considered and must be systematically sought for all capabilities which are essential but which cannot be obtained at national level," he told the EDA's in-house journal, European Defence Matters.

Over the past decade, France initially sought defense partners inside the EUuropean Union but found itself became frustrated with Germany's more cautious view of military power. However, Paris has though been forging closer military and industrial ties with London since the two sides signed a defense cooperation treaty in 2010.

That cooperation has included Britain providing airlift and battlefield surveillance capabilities for French troops fighting in Mali, while France has sent maritime patrol aircraft to Scotland to hunt suspected Russian submarines close to a UK nuclear missile submarine base.

De Villiers accepts that as defence is one of the "fundamental prerogatives of the state" cooperation requires a "strong will to get closer to others."

The defense chief's De Villier's call is echoed by the EU high representative of the Union for foreign affairs and security policy EU High Representative for Foreign Affairs and Security, Federica Mogherini, who said a more "cooperative approach" is needed to reverse a trend that has seen spending in defense research and technology fall by almost 30 percent in recent years.

"Cooperation needs to be incentivized," she said. "We must make the best use of all EU instruments and policies at our disposal in support of an integrated and sustainable industrial base which will help increase Europe's autonomy and ability to act with partners." she said.

Voicing the European industry standpoint, Jan Pie, secretary-general of the AeroSpace and Defence Industries Association of Europe (ASD), said, "ASD shares the concern about the lack of cooperation and fully supports every effort to foster and enhance European defense cooperation."

However, with defense is still a closely guarded competence of EU member states and any moves toward closer cooperation at the EU level will is sure to spark resistance a furious response in some quarters.

Mike Hooken, a member of the European Parliament and defense spokesman for the UK Independence Party, said: "When the EU says 'deeper cooperation,' what they actually mean is a wholesale takeover of yet another aspect of our sovereignty," said Mike Hooken, a member of the European Parliament and defense spokesman for the UK Independence Party. "The first duty of government in the UK is the defense of the realm. To hand any of our military capability to an unelected, dictatorial body like the EU is little short of treason.

"Having seen what a total mess the EU has made of both the euro and the immigration policies, I have very grave concerns about their ability to mount any form of military operation, never mind manage an army and defend the UK against a growing range of threats."

Andrew Chuter contributed to this report from London.