Josep Borrell also said that former U.K. Prime Minister David Cameron had "gambled" with his country's future | Tomas Vitas Spanish foreign minister: UK will split before Spain Josep Borrell says he is ‘very much more worried’ about the UK’s unity than Spain’s.

The U.K. is more likely to break apart over Brexit than Spain is over the secessionist aspirations of some in Catalonia, said Spain's foreign minister.

In an wide-ranging interview with POLITICO's Ryan Heath, Josep Borrell also said that former U.K. Prime Minister David Cameron had "gambled" with his country's future. And he reiterated Spain's insistence that negotiations over the future relationship between Gibraltar and the EU should be handled separately to those with the U.K.

"I am very much [more] worried about the unity of the United Kingdom than the unity of the Kingdom of Spain. I think the United Kingdom will split apart before the Kingdom of Spain," he said, in an apparent reference to movements in both Scotland and Northern Ireland to leave the U.K. over its EU departure.

On Brexit, Borrell said his government wants a clear statement that no future deals on the U.K.'s relationship with the EU after it leaves the bloc would apply to Gibraltar — a disputed territory on Spain's south coast — without Spain's consent.

"Negotiations between the U.K. and EU do not apply to Gibraltar," he said, adding that these negotiations should be separate.

"Cameron played poker with his country at least twice: on Scotland and on Europe" — Josep Borrell

“We have been working with this premise and the Council has approved [this approach] at least three times,” Borrell said.

"There will be specific negotiations about Gibraltar between the European Union and the United Kingdom but for these agreements Spain … has to agree," he added, "It was in the text and suddenly it appears that it is not so clear."

Spain’s Socialist Prime Minister Pedro Sánchez has also adopted a tough stance on the Gibraltar issue. Speaking at an Economist summit in Madrid on Tuesday, he said: “As of today, if there are no changes with respect to Gibraltar, Spain will vote no to the agreement on Brexit.”

Spain's minority government has come under attack from the conservative opposition for failing to use the opportunity presented by Brexit to take back control of Gibraltar.

On the question of a second Brexit referendum, which is gaining more traction in the U.K. because of widespread opposition to May's deal, Borrell said he is opposed: "I don’t like second referendums ... It’s something that doesn’t look very democratic."

But he did comment on Cameron's decision to hold a referendum in the first place. "Mr. Cameron will not pass into history as the best prime minister in the history of Britain," said Borrell, "Cameron played poker with his country at least twice: on Scotland and on Europe."

He had kinder words about May though. "As far as I know she looks like being a quite resilient woman, someone who is really tough and having a strong stance and resisting," he said.

On the Catalan crisis, Borrell said his government is not more likely to allow for a “referendum of secession” than the previous government of Mariano Rajoy. “I am not [David] Cameron and we are not Britain, it is not going to happen.”

“No constitutional government will allow for it, because it is against the constitution,” he added.