President of the European Council Donald Tusk looks on during a joint news conference with Sweden's Prime Minister Stefan Lofven (unseen) at the government headquarters Rosenbad in Stockholm, Sweden, September 9, 2016. Marcus Ericsson/TT News Agency via REUTERS ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. FOR EDITORIAL USE ONLY. SWEDEN OUT. NO COMMERCIAL OR EDITORIAL SALES IN SWEDEN. NO COMMERCIAL SALES. Image Credit: REUTERS

European political leaders, minus United Kingdom Prime Minister Theresa May, meet today in Bratislava, Slovakia, to develop a post-Brexit vision for the continent’s future with the 60th anniversary of the Treaty of Rome early next year. This is a potentially difficult and divisive agenda for the remaining 27 states, and one key focal point of discussion will therefore be on an area where there is broad consensus: Enhancing security and border protection to emphasise the resilience and integrity of the continuing European Union (EU) project.

EU internal and external security policy has come under intensified focus with recent terrorist atrocities in the continent; the ongoing migration crisis; and also Russia’s assertive posture. European Council President Donald Tusk has said that “people expect that the EU after Bratislava will again be a guarantor of stability, security and protection”. Moreover, there is also an added political ‘window of opportunity’ to move forward on this agenda with High Representative of the EU for Foreign Affairs and Security Policy, Federica Mogherini, having launched in June a new global strategy on foreign and security policy, the first such European document since 2003.

Several leading politicians, including Italian Prime Minister Matteo Renzi, have already called for a “European pact for freedom and security”. This highlights that a carefully-crafted package of measures, including greater EU intelligence cooperation and strengthening Europe’s border force, could secure not just high-level political traction, but potentially chime with the public mood too.

More potentially controversial, however, is greater defence cooperation with the debate over this issue dating back to at least the 1950s when an initiative to form a European Defence Community failed to see the light of day. Today, however, the impulse towards greater integration is being driven by Russian assertiveness and financial pressure on national defence budgets. And Brexit could now also eliminate a long-standing obstacle to greater European cooperation in this area, given that the United Kingdom government has long been opposed to deeper defence integration.

One signal of potential movement came in March when European Commission President Jean Claude Juncker asserted that the EU needs its own army, a proposal welcomed by German Defence Minister Ursula von der Leyen, so Europe can “react more credibly to the threat to peace in a member state or in a neighbouring state”. While such an army is at best a longer-term aspiration, plans are being drawn up for so-called “structured cooperation” between willing EU states to develop common centres of military planning, material and personnel.

Beyond this, key contentious issues such as migration and the upcoming Brexit negotiations themselves will not be on the formal agenda. Instead, there will be what is being billed as a brainstorming session on how the EU can best project itself at a time of major concern about globalisation.

One of the reasons for the informality of this session is that EU officials want to downplay expectations that concrete proposals will emerge from the meeting. Instead, there will be continuing dialogue on this agenda in the next six months, including at the next scheduled EU summit, which will include the UK prime minister, on October 20-21 in Brussels, plus another more informal meeting like Bratislava, without her, in Malta in February.

As European leaders are beginning to plan beyond Brexit, potentially the worst reversal for the EU in its more than half century history, there is significant disagreement on the best way forward. Some senior decision-makers, including Juncker, favour a stronger integrationist response in key areas, but recognise the sensitivities of this, especially given the 2017 French and Germany national ballots.

Other policymakers, including Dutch Finance Minister Jeroen Dijsselbloem, the Chair of the Eurogroup of Finance Ministers, have argued for caution, asserting that if the “negative outcome of the UK referendum should be interpreted as a vote against Europe, it doesn’t make sense in my view to respond immediately by asking for more Europe” in the form of a new, potentially grand integration schemes, including on the economic front. Scepticism of the wisdom of further economic integration is echoed in the French and German Governments given the significant potential for popular backlash against such a move ahead of the 2017 national elections there.

In Paris, for instance, there is concern that further controversial EU initiatives could provide a fillip to the far-right National Front’s Marine Le Pen, who is currently riding high in opinion polls and who has promised a referendum on French membership of the EU (so-called Frexit) if she is elected the country’s president. Moreover, further economic integration could be divisive between the 19 core Eurozone states and the other eight EU members.

Another key, thorny issue that will need to be resolved in the coming months is the concern in Brussels and some European capitals over how the UK’s departure will potentially significantly disrupt for years to come the 27 member states’ balance of power, inner workings and policy orientations. Amongst some of the smaller EU states, a particular fear is that the loss of the United Kingdom as a member will ultimately consolidate the influence of other large states, especially Germany.

It is therefore noteworthy in the build-up to Bratislava that key blocs of countries last week met to build common responses to the EU’s future. This includes leaders of the EU’s southern countries, including Greece, Malta, Cyprus and Portugal, who met last Friday in Athens and the so-called Visegrad Group — Hungary, Slovakia, Poland and Czech Republic — convened in Krynica.

Taken overall, EU political leaders are still scrambling to come to terms with the Brexit vote, which will continue to set the political weather across the continent for months to come. Decisions taken in the coming weeks, including on the security and defence front, will define the longer-term political and economic character of the EU in the face of the divisions still remaining about how best to respond to what could be the union’s most significant ever setback.

Andrew Hammond is an Associate at LSE IDEAS (the Centre for International Affairs, Diplomacy and Strategy) at the London School of Economics.