Britain's shock vote to leave the European Union—the first time a member state has chosen to pull out—has reversed the post-World War II unification process that has underpinned peace and prosperity on the continent, Reuters report.
The loss of Europe's second-biggest economy and one of its two main military powers triggered a scramble to shore up the remaining 27-nation bloc, amid a rising tide of eurosceptic populism, rather than any radical move toward closer union.
Despite months of seesawing opinion polls, few in the top echelons in Brussels, Berlin or Paris believed voters would ultimately risk a so-called Brexit.
WATCH: Britain Votes to Leave EU in Brexit Vote
British exit negotiations could be long and divisive. "Brexit will oblige some countries to take a decision. They can't stay one foot in and one foot out," former Italian Prime Minister Enrico Letta told Reuters, citing the four central European countries that form the so-called Visegrad group, as well as Denmark and Sweden.
Anti-EU nationalists around Europe, energized by the British Leave campaign that took on and defeated the political and business establishment, are already demanding their own referendums on EU membership or on whether to abandon the euro.