In March 2017 the European Union (EU) will mark the sixtieth-anniversary of the signing of the Treaty of Rome which established the European Economic Community from which it has evolved. The flows of people coupled with security fears after the Paris and Brussels terrorist attacks and a lack of solidarity in EU member states are putting pressure on the EU's border-free travel and leading to sharp divisions amongst member states. In June 2016, British electors vote in a referendum on whether or not the UK should remain in the EU, on the basis of the deal approved at the meeting of the European Council on February 2016. Europe's fears of migration and ISIS have become entangled with its deteriorating relationship with Vladimir Putin's Russia following his annexation of Crimea in 2014. The EU member states have stuck together to maintain sanctions on Russia but more economic assistance should be forthcoming to help Ukraine defend itself against unremitting pressure from Russia.