The tiny British territory of Gibraltar has become the next Brexit battleground

When British Prime Minister Theresa May formally triggered Brexit last week, observers knew it would send the relationship between Britain and the EU into rocky, uncharted terrain. But few would have expected any talk of war.

That’s what has happened since a draft document of EU negotiating guidelines for Brexit talks Friday raised questions about the future of Gibraltar, a tiny British overseas territory on the southern tip of Spain that Madrid has long sought to have returned to its control.

The dispute was sparked by a clause in a paper — sent by European Council President Donald Tusk to EU member states Friday — that said Gibraltar could be included in future trade deals between London and Brussels only with Spain’s express permission.

“After the United Kingdom leaves the Union, no agreement between the EU and the United Kingdom may apply to the territory of Gibraltar without the agreement between the Kingdom of Spain and the United Kingdom,” read the clause in the 9-page document outlining the bloc’s opening position for Brexit negotiations.

The prospect of Spanish interference with Britain’s sovereignty in Gibraltar caused alarm in the U.K., which was ceded the 2.6-square-mile (6.7-square-kilometre) peninsula under a 1713 treaty and has repeatedly butted heads with Spain over the territory in the centuries since. About 30,000 people live in Gibraltar, British citizens who govern their own affairs except in matters of foreign policy and defense. Gibraltarians have voted overwhelmingly in two referenda against any form of Spanish sovereignty, including a proposal for shared sovereignty of the peninsula in 2002.

Tensions ratcheted up Sunday when Michael Howard, a former leader of the ruling Conservative party, cited the 1982 Falklands War with Argentina in describing the lengths he believed the government would go to defend Gibraltar’s sovereignty.

“Thirty-five years ago this week, another woman prime minister sent a task force halfway across the world to defend the freedom of another small group of British people against another Spanish-speaking country, and I’m absolutely certain that our current prime minister will show the same resolve in standing by the people of Gibraltar,” Howard told Sky News Sunday.

About 900 people were killed in fighting in 1982 after Argentina invaded the Falklands, a British possession in the South Atlantic, and Britain sent a naval force to reclaim them.

Howard’s bellicose talk drew criticism at home and abroad, with Liberal Democrat leader Tim Farron saying, “In only a few days, the Conservative right are turning long-term allies into potential enemies.”

A spokesman for May did not condemn the remarks and instead said that Howard’s comments merely sought to convey the resolve that Britain would demonstrate in defending Gibraltar, although he ruled out any military approach. Speaking to reporters on a flight to Jordan Monday, May laughed off talk of war with Spain, saying the issue would be resolved through negotiations.

But the tone of Howard’s comments has raised concerns in Spain. Foreign Minister Alfonso Dastis responded to the furor Monday by urging the British government to calm down.

“Someone in the U.K. is losing their cool, and there’s no need for it,” he said, following a pre-arranged meeting with the U.K.’s Brexit minister David Davis. “Making comparisons with past situations like the Falklands is a little out of context. The Spanish government is a little surprised by the tone of comments coming out of Britain, a country known for its composure.”

Gibraltar’s Chief Minister, Fabian Picardo, has also weighed in on the heated debate. He told Reuters that the inclusion of the clause was “Spanish bullying,” and described European Council President Donald Tusk as “behaving like a cuckolded husband who is taking it out on the children.”

British soldiers fighting alongside the Dutch first captured the “Rock,” as Gibraltar is known, in 1704, before sovereignty was formally ceded under the Treaty of Utrecht nine years later. Spain has repeatedly called for the return of Gibraltar, a strategically important outpost at the entrance to the Mediterranean, as it views British sovereignty there as an affront to its territorial integrity. Its current push to have influence over the territory is also motivated by the low corporate tax rate that has made Gibraltar a global hub for the financial services sector.

A standoff looms over Gibraltar amid the wider negotiations to remove Britain from the EU and sign new deals on issues such as trade and security with the bloc. Brussels has indicated the draft negotiations blueprint that sparked the dispute has the full backing of European member states, and there is no appetite to back down, although the draft guidelines will be revisited by EU leaders later in April.