BRUSSELS — Britain and the European Union (EU) finally began formal Brexit negotiations yesterday, vowing to work constructively for a deal despite disarray in London over whether to go for a “hard” or “soft” divorce.

Almost exactly a year after Britain’s seismic referendum to leave the bloc, the EU’s chief negotiator, Mr Michel Barnier of France, welcomed his counterpart, Mr David Davis, with a cheery handshake at the European Commission in Brussels.

The smiles belied the fact that at stake is not just Britain’s future, but Europe’s postwar political order and its place in the world, which could be fatally undermined without an agreement by the March 2019 deadline.

“We must first tackle the uncertainties caused by Brexit,” Mr Barnier said, citing the rights of EU citizens in Britain and the possible impact on the open border between Northern Ireland and Ireland.

“I hope today we can identify priorities and a timetable that would allow me to report to the European Council (summit) later this week that we had a constructive opening of negotiations,” added the former European commissioner and French foreign minister, speaking against a backdrop of British and EU flags.

A key issue he did not mention was the EU’s bill for Britain to leave, which Brussels estimates at a colossal €100 billion (S$155 billion). Mr Davis, a prominent tough-talking figure in the “Leave” campaign, sounded a positive note, saying that while there would “undoubtedly be challenging times ahead”, he wanted a good relationship with the EU.

“There is more that unites us than divides us”, Mr Davis said, referring to the latest reported terror attack overnight in London and the loss of lives in forest fires in Portugal. “We launch negotiations in a positive and constructive tone, determined to build a strong and special partnership between ourselves and our European allies and friends in the future.”

European stocks rose yesterday, partly on optimism about the talks getting under way after months of uncertainty, analysts said.

In Berlin, German Chancellor Angela Merkel emphasised the unity of the remaining 27 EU countries, which have been alarmed in recent weeks by Prime Minister Theresa May’s threats to walk out of the talks.

“I would like us to get a good agreement that is in both sides’ interests. But the 27 of us will formulate our interests very clearly and hopefully, together,” Ms Merkel said.

Worried by immigration and loss of sovereignty, Britons voted last year to end their country’s four-decade membership in the 28-country bloc — the first nation ever to do so.

Mrs May triggered the two-year Brexit process in March when she was riding high in opinion polls, and called fresh elections shortly after to shore up her mandate for a tough Brexit stance. But she lost her parliamentary majority, putting that hard-line approach and her political future in doubt after the disastrous June 8 election.

Britain now appears to have given in to the EU’s insistence that the negotiations first focus on three key divorce issues, before moving on to the future EU-United Kingdom relationship and a possible trade deal.

Those issues are the exit bill; the rights of three million EU nationals living in Britain and the one million Britons on the continent who currently are allowed to live, work and claim welfare benefits; and the status of the border between Northern Ireland and Ireland.

Mrs May herself will also have a chance to update the other 27 EU leaders on her Brexit plans at a summit meeting in Brussels on Thursday. AFP