Keir Starmer has been told he must not surrender Gibraltar, after Spain’s foreign minister re-opened the contentious debate over the rock’s sovereignty. Speaking to BBC Newsnight, the country’s foreign minister said the status of Gibraltar is “not resolved yet”.

Speaking to the BBC’s flagship interview show, minister José Manuel Albares said he wants to “solve the issue of Gibraltar in order to have a full European Union-UK relationship".

He added: "The relationship between the UK and EU is a comprehensive relationship, not a pick and choose relationship." The comments immediately sparked backlash from British politicians, attacking Keir Starmer’s previous diplomatic weakness as causing the new intervention by Spain.

Shadow Foreign Secretary Priti Patel warned: “Given that whenever Labour negotiates, Britain loses, it’s no wonder Spain sees this weak government as an opportunity.”

"Gibraltar is British, end of, and we will remind the government exactly where the sovereignty of Gibraltar lies.”

Reform UK’s Richard Tice added: “Labour have already agreed to give away the Chagos islands in one of the worst deals in history. For once they need to stand up for Britain and our overseas territories.

“Quite simply we need to tell the Spanish no means no. Gibraltar is not up for discussion and never will be. A Reform UK government would stand up for Gibraltar and take back the Chagos islands.”

Last September, Foreign Secretary David Lammy sparked fury after pledging a “deal on Gibraltar” with the EU.

Mr Lammy said he had welcomed Spain’s foreign minister Jose Manuel Albares to London, where they “covered the full spectrum of our vital partnership”.

He then added: “We also looked ahead to meeting in Brussels later this week to seek to progress a deal on Gibraltar alongside [chief minister Fabian Picardo] and [EU Commission Vice-President] Maros Sefcovic."

In July, David Lammy reaffirmed the Government’s “double-lock” commitment on Gibraltar’s British sovereignty during his first phone call with Mr Picardo.

However senior Tory Mark Francois pointed out that the last Labour Government attempted to surrender the key overseas territory.

He warned: “It was inevitable that after the abject surrender of the Chagos Islands - for that is what it is - the Spanish would try and exert pressure on Gibraltar.

“Under Blair, Labour tried to sell [Gibraltar] out for joint sovereignty, and a referendum killed it. So as we couldn’t trust you on Gibraltar before, why on earth - after what you’ve done to Chagos and the Chagosians - should we trust you now?”

The Foreign Office has been approached for comment.