Starmer will meet on Monday with EU chiefs for the first post-Brexit EU-UK summit aimed at agreeing steps towards a closer relationship between Britain and the 27-country bloc which it left five years ago after an acrimonious and knife-edge referendum.

"This week, the prime minister will strike yet another deal that will deliver in the national interest of this country," Downing Street said in a statement, also pointing to recent trade deals with the United States and India.

Starmer will welcome EU bosses Ursula von der Leyen and Antonio Costa as well as top EU diplomat Kaja Kallas for Monday's talks at the storied Lancaster House venue in London.

"The prime minister will set out how a strengthened, forward-looking partnership with the European Union will deliver for working people and lead to more money in pockets," the statement said.

Talks looked set however to go down to the wire due to last-minute squabbling over long-standing issues, such as fishing rights and food checks.

But negotiators were hopeful of at least signing a defence and security partnership.

Starmer, elected Labour prime minister last July, wants a deeper relationship with the European Union than the one negotiated by the previous Conservative government.

That deal "isn't working for anyone", Starmer's office said.

The move is aimed at opening the door to closer cooperation as both the EU and Britain race to rearm in the face of the threat from Russia and fears the United States under President Donald Trump will no longer help protect Europe.

That should mean more regular security talks, Britain considering joining EU military missions and the potential for London to fully tap into a 150-billion-euro ($167-billion) defence fund being set up by the bloc.

But Starmer has several red lines he has said he will not cross, while sticking points remain over some EU demands that threaten to stall the rapprochement.

- 'Significant moment' -

In an interview with The Times on Saturday, Starmer said a deal would be a "really significant moment".

Starmer has ruled out rejoining the customs union and single market but has suggested that the UK is ready for regulatory alignment with the EU on food and agricultural products.

EU diplomats in Brussels have been working on getting Britain to keep its waters open for European fishermen in return for easing the checks on some food imports from the UK.

And Starmer appeared to have made a key concession by agreeing to an EU demand and clearing the way to let young Europeans live and work in Britain under a youth mobility scheme.

While freedom of movement was a "red line," he told The Times, "youth mobility is not freedom of movement".

Starmer is approaching the scheme cautiously under pressure from rising support for Nigel Farage's anti-immigration and Euro-sceptic party Reform UK, which made huge gains in local elections earlier this month.

Starmer said late Saturday in a statement that on Monday "we take another step forwards, with yet more benefits for the United Kingdom as the result of a strengthened partnership with the European Union".

"In this time of great uncertainty and volatility, the UK will not respond by turning inwards, but by proudly taking our place on the world stage."