Sir Keir Starmer will today accept an invitation to take part in an EU defence summit, the first time a British PM will have attended a leader’s meeting since Brexit. 

He will be formally asked to attend by European Council president Antonio Costa when they meet in Downing Street this afternoon.

It comes as the PM continues efforts to ‘reset’ the UK’s relationship with the EU.

The Prime Minister’s meeting with Mr Costa comes just days after Chancellor Rachel Reeves joined European finance ministers in Brussels.

Foreign Secretary David Lammy has also met his EU counterparts in recent weeks.

A No10 source told the Financial Times the PM would accept an invitation to have dinner during an ‘informal retreat’ in Belgium on February 3. 

On Monday, Ms Reeves told her eurozone counterparts she wanted to ‘rebuild those bonds of trust that have been fractured in the last few years under the previous government and to show our friends, neighbours and allies in the European Union that we want a reset of those relationships’.

But she bluntly said there were no plans to rejoin EU institutions like the Single Market or Customs Union.

Although Sir Keir has attended – and the UK has hosted – EU leaders as part of the wider European Political Union, the dinner will be the first time a PM has joined his or her EU counterparts since Brexit.

Sir Keir and Mr Costa are expected to meet in Downing Street on Thursday afternoon to discuss the Prime Minister’s hopes for a closer relationship with the EU after the acrimony of the Brexit battles.

Details of Mr Costa’s trip to London were published on the European Council’s website.

As well as the post-Brexit relationship, the talks between Sir Keir and Mr Costa could cover wider global issues including the situation in Syria.

However, Labour’s attempt at détente could still run into problems.

Earlier this week Ms Reeves was told Britain will have to cave into EU demands for greater fishing access and freedom of movement in exchange for closer trading ties.

During her visit to Brussels, the Chancellor was told that greater access to UK waters for EU trawlers and a youth mobility scheme will be ‘on the table’ in future talks.

It came ahead of a summit with EU finance ministers, making Ms Reeves the first British Chancellor to attend such a meeting since the UK left the bloc almost five years ago.

Her attendance was designed to be a statement of intent, with the Chancellor among a group of Cabinet Ministers pushing the hardest for a ‘reset’ in relations with the bloc.

She told them that ‘breaking down barriers to trade’ would be a key goal in future talks to boost economic growth on both sides of the Channel.

In a speech to them, she added: ‘In the long-run, Brexit is expected to cause UK trade intensity to fall by 15 per cent.

‘And with goods exports between both the UK and EU continuing to remain below 2018 levels, this is impacting UK and EU economies alike.

‘And so, the reset in relations is about doing what is in the best interests of our shared economies.’

But ahead of the summit, Spain’s Cabinet Minister for the economy and trade, Carlos Cuerpo Caballero, warned greater market access would come at a price.

Asked if greater access to UK fishing waters would be a red line, he said: ‘There is an element of common understanding that there’s a win-win situation of going further in this relationship between both parties.

‘And we need to engage…on what would be the next steps towards getting back as much as possible to where we were [before Brexit] in terms of those financial economics and trade ties.

‘It’s of course agriculture, it’s of course fisheries, it’s of course migration as well. There are many elements on the table that we will need to discuss.’

Asked if a youth mobility scheme was also a ‘red line’, he added: ‘Well, that’s an important element from the EU side we want to put on the table.

‘And that’s one of the areas where I think there is greater value added, also for the UK, to engage constructively.’

UK ministers fear a youth mobility scheme, which would allow young people from across the EU to live and work in Britain for a set period, would be seen as Labour bringing back a form of free movement.