EU leaders said Friday they will look more closely at defence as a changing world and tight budgets force member states to cooperate in search of a bigger bang for their euros. Taking up the issue for the first time since 2008, they said the bloc "is called upon to assume increased responsibilities in the maintenance of international peace and security." This in turn will help "guarantee the security of its citizens and the promotion of its interests," a statement said after a two-day summit. To achieve that goal, member states will have to come together to fund increasingly expensive defence projects which are now beyond the means of most. Leaders "stressed that financial constraints highlight the urgent necessity to strengthen European cooperation... in order to develop military capabilities," the statement said. Do that and there are wider benefits possible for "employment, growth, innovation and industrial competitiveness within the European Union." In separate remarks, EU President Herman Van Rompuy said there were several reasons for having put defence back on the summit agenda. "The security challenges that Europe faces have, if anything, increased over the last few years," Van Rompuy said, adding that the Libyan campaign last year had shown up "certain gaps that we need to fill in." Member states have slowly but steadily ceded more powers to EU institutions over the years in managing the economy, a process the debt crisis has speeded up, and it now seems that defence has entered into the equation too. In 2004, the EU set up the European Defence Agency to promote such cooperation, focussing on building up defence capabilities. EDA chief executive Claude-France Arnould wrote earlier this year that EU defence departments were "facing a perfect storm," as funding fell and the world became more unstable. In addition, Washington was turning towards Asia, causing some unease over its defence commitment to Europe, and the defence industry was "struggling" to retain technical know-how as major programmes were cut or delayed. Arnould noted that while "the political will among member states has never been stronger, translating this will into direct positive action is complex." Her point is well made -- Western defence officials repeat as a mantra the need to share the burden but will at the same time stress the imperative for national governments to have the last word on what is done. Smaller projects with fewer partners tend to work better, they say, but have a limited impact whilst the larger ones -- for a tank or aircraft system -- quickly stir national passions given the huge costs involved. After the EDA, the EU set up its European External Action Service in 2010, designed to give it a distinct voice in foreign affairs. With the higher profile diplomatic presence, military considerations inevitably come into play, with the EU taking on a series of commitments, among them the Balkans and anti-piracy operations off the Horn of Africa. Against this backdrop, EU leaders invited EEAS head Catherine Ashton, the EDA and the European Commission "to develop further proposals and actions to strengthen (the EU's) Common Security and Defence Policy and improve the availability of the required civilian and military capabilities." The three are to report back by September 2013, with the aim of preparing submissions for the December EU leaders summit of that year.