The leaders of 27 EU countries are meeting in Bratislava, Slovakia after Britain’s vote to leave the bloc on June 23rd.
Germany’s Angela Merkel and France’s François Hollande say the EU must do more to protect its external borders and bolster its defence capacity.
But legally, since the UK remains a full member, this meeting is an informal one and no binding decisions can be taken.
There is a huge debate in Brussels and beyond over how much power should rest in the hands of EU institutions and how much should be transferred back to national capitals.
European Council president Donald Tusk has been on a shuttle diplomacy tour over the past weeks to sound out heads of state and government.
In a letter sent out prior to the meeting, Tusk warned leaders that it would be a mistake to think that British voters were the only ones with serious concerns about the European Union.
“People in Europe want to know if the political elites are capable of restoring control over events and processes which overwhelm, disorientate, and sometimes terrify them. Today many people, not only in the UK, think that being part of the European Union stands in the way of stability and security,” wrote Tusk in the letter published on Tuesday.
The next EU summit, with all 28 countries, will be held in Brussels next month.