Under a pact that excludes the United Kingdom, in view of Brexit, 25 European Union countries agreed on March 6 to develop their first joint defence projects. Now Britain – one of Europe’s biggest military powers – feels left out.

But while Britain may be central to European security efforts, it has long blocked defence integration, fearing the creation of an EU army.

British Prime Minister Theresa May wants to reach a “security treaty” with the EU by 2019.

As reported by the Reuters news agency, defence ministers from the pact’s signatory states, which comprise all but three of the current EU members, signed off in Brussels on 17 collaborative projects. These include a European armoured infantry fighting vehicle, underwater anti-mine sensors and a European medical command.

The eventual aim of the Permanent Structured Cooperation pact is to develop and deploy forces together, backed by a multi-billion-euro fund for defence research and development that is now under negotiation.

Denmark, which has opted out of most EU military matters, and neutral Malta are the others not taking part.

Also, any decision on whether to allow non-EU countries to join future defence projects will be delayed until the end of the year.

According to Reuters, one senior EU official said ministers want to see more progress in Britain’s exit negotiations with Brussels given the sensitive nature of defence cooperation with London.