LONDON — Britain sought to downplay a row over future security ties with the European Union (EU) yesterday, as London and Brussels drew up the first battle lines at the start of their two-year divorce proceedings.

France and Germany also put up a common front against Prime Minister Theresa May’s call to negotiate the exit and the new relationship at the same time, setting up a major stumbling block before negotiations even begin.

But a day after Mrs May formally notified the EU of Britain’s intention to leave, it was her warning that failure to clinch a deal on trade would weaken the fight against terrorism that rankled.

“It’s not a threat,” Brexit minister David Davis told BBC radio after warnings from Brussels against using security as a bargaining chip in the talks. He said the “simple truth” was that without a “parallel deal” with the EU, Britain would no longer be a member of the Europol crime-fighting agency or take part in the European Arrest Warrant system.

“We want a deal, and she was making the point that it’s bad for both of us if we don’t have a deal,” Mr Davis said. “Now that, I think, is a perfectly reasonable point to make and not in any sense a threat.”

Interior Minister Amber Rudd noted that Britain was the top contributor to Europol, adding: “If we left Europol, then we would take our information ... with us”.

Britain is a European security powerhouse — one of only two nuclear powers in the bloc and with some of the world’s most capable intelligence services. The European Parliament’s chief Brexit negotiator, Mr Guy Verhofstadt, said that “citizens’ security was far too serious a subject” to be held hostage to negotiations.

Ms Sylvie Bermann, France’s Ambassador to Britain, echoed that sentiment, telling the BBC that there “can’t be a trade-off” between trade and security. “I don’t understand that because it wouldn’t be in the interest of the UK because we’re all facing the same security challenges,” she said.

The row came as some of the EU’s top leaders fleshed out their strategy for the hard talks ahead, as the bloc reels from the blow of one of its biggest members becoming the first state ever to start withdrawal from the 60-year-old union.

The path ahead is strewn with obstacles. French President Francois Hollande yesterday followed German Chancellor Angela Merkel in rejecting Mrs May’s proposed structure for the negotiations, saying the exit agreement should come first. “First we must begin discussions on the modalities of the withdrawal, especially on the rights of citizens and the obligations arising from the commitments that the United Kingdom has made,” said Mr Hollande.

“On the basis of what progress is made, we could open discussions on the framework of the future relations between the UK and the EU.”

The fate of three million EU citizens living in Britain and one million British people within the bloc’s nations is at the top of leaders’ agenda. Also looming large is the so-called “exit bill” Britain will have to pay, estimated to be as much as €60 billion (S$89.8 billion).

European Council President Donald Tusk is due to issue draft “negotiating guidelines” today, and leaders of the 27 remaining EU countries will hold a special summit on April 29 to rubber stamp the plans. AGENCIES