EU foreign policy chief Federica Mogherini hailed the decision as a "historic moment in European defense". Whereas Ireland, Portugal and Malta have not yet decided whether to join the initiative, Denmark and the United Kingdom are not expected to participate. The EU, however, also stressed that PESCO is complimentary to North Atlantic Treaty Organisation, in which 22 of the EU's 28 countries are members.
Defense and foreign ministers from the 23 countries signed a notification of their intention to establish the Permanent Structured Cooperation (PESCO), which allows countries to cooperate more closely on security operations and building up military capability.
On November 13 ministers from 23 EU member states signed a joint notification on the Permanent Structured Cooperation (PESCO) and handed it over to the High Representative and the Council, Armenpress reports citing the EU Council's official website.
The Permanent Structured Cooperation on defence agreement (Pesco) seeks to improve European Union coordination on defence and weapons systems development.
The agreement is part of efforts led by Germany and France to reboot the European Union after Britain's decision to leave and follows the announcement in June of a 5.5-billion euro European Defence Fund. "The real problem is not how much we spend, it is the fact that we spend in a fragmented manner".
This has led to unease by European allies that the USA was not committed to the alliance's mutual defense pact.
"We are agreeing on the future cooperation on security and defence issues ... it's really a milestone in European development", he added.
Mrs Mogherini said the move would not only complement Nato's security aims but fill in gaps in the Atlantic alliance. "I think that European cooperation on defense questions will rather contribute to saving money - we have about 50 percent of the United States' defense spending in Europe, but only 15 percent of the efficiency". At launch the focus will be project-driven such as the development new military equipment such as tanks or drones.
The agreement also commits countries to "regularly increasing defense budgets in real terms" as well as devoting 20 percent of defense spending to procurement and two percent to research and technology.