Sir Keir Starmer’s government will adopt a policy of “ruthless pragmatism” and is willing to “fight” its opponents as it seeks to deepen economic relations with the EU, the minister in charge of Britain’s relations with the bloc said on Tuesday.

Nick Thomas-Symonds told an audience in Brussels that he was seeking an “ambitious” outcome of talks, which will come into focus at an EU-UK leaders’ summit on May 19.

People briefed on the summit say it will take place in the UK, putting post-Brexit relations with the EU firmly in the spotlight. Brexit-supporting newspapers are already warning of a Starmer “surrender”.

Thomas-Symonds, who normally peppers his speeches with references to Labour’s “red lines” in any EU negotiation, struck a much more positive tone when addressing the EU-UK Forum annual conference.

“The time for ideologically-driven division is over — the time for ruthless pragmatism is now,” he said, against a backdrop of opinion polls showing public support for Brexit has fallen sharply.

A YouGov survey last week, published on the fifth anniversary of the UK’s post-Brexit trading deal coming into force, found that just 30 per cent of Britons now say it was right for the UK to leave the EU, compared with 55 per cent who say it was wrong.

In a sign that ministers are willing to take on Eurosceptic critics in pushing for an improved EU relationship, Thomas-Symonds cited a speech by chancellor Rachel Reeves last week: “Growth won’t come without a fight.”

Starmer was in Brussels on Monday night for dinner with the EU’s 27 leaders, the first time a British premier has attended a meeting of the European Council since Brexit.

After the meeting, Council president António Costa surprised British officials by letting slip that a long-planned EU-UK summit would take place on May 19. “We hadn’t expected that,” said one British official.

The summit will take place in Britain after local elections on May 1, although Starmer is certain to feel the political heat as he starts to explore options for strengthening UK economic and security ties with Brussels.

Thomas-Symonds set out familiar objectives such as lowering barriers to trade in food, alongside defence and security co-operation. But ministers are also exploring ideas such as linking the EU and UK carbon markets and a limited form of pan-European customs agreement.

The summit is seen as an important moment in negotiations with the EU — but not the end point. Brussels is seeking a number of concessions from Starmer, including continued access to British fishing grounds and a youth mobility scheme.

Nigel Farage, leader of the resurgent pro-Brexit Reform UK party, said on Tuesday that Starmer had committed “an act of humiliation” by attending Monday’s dinner at the Palais d’Egmont.

It was in the same palace where Conservative prime minister Edward Heath signed the treaty taking Britain into the European Economic Community — a forerunner to the EU — in 1972.

Starmer’s “red lines” prohibit Britain from rejoining the single market or customs union, or readopting free movement, severely limiting any potential economic gains from a deal with the EU.

Maroš Šefčovič, the EU commissioner in charge of UK talks, told the conference the Brexit treaties signed by the last Conservative government were “excellent”, but were “a solid base on which we can build further”.