The UK, the US and other non-members will be allowed to participate in future European Union (EU) defence projects to develop aircraft, helicopters and weapons.

Reuters reported three EU diplomats as saying that non-members will be allowed to participate under an ‘exceptional basis’.

Non-member countries will be allowed only on individual projects and must bring expertise to the projects.

This decision follows a long-standing discussion if the UK will be allowed to participate in the Permanent Structured Cooperation (Pesco ), a new EU defence pact, following Brexit.

PESCO was officially launched in November 2017 and is the part of the EU’s security and defence policy (CSDP).

It helps increase defence cooperation among the participating member nations and deliver capabilities that will improve security to EU citizens.

In May, the EU proposed to set aside €8bn from the budget for a new and complementary EU defence fund.

As reported by the news agency, the EU has 178 weapon systems in total. In comparison, the US, which is said to be the biggest military power in the world, owns 30.

A senior EU diplomat was quoted by Reuters as saying: “The rules on participation of non-members was the last missing piece of the puzzle.”

A second diplomat stated that Turkey may not be allowed to take part.

Last month, Serbia suspended all military exercises with foreign partners for six months.