Spain has threatened to call off Sunday's European Union summit on Brexit, unless an agreement is made with the UK over Gibraltar.

Spanish Prime Minister Pedro Sanchez told a news conference on Friday: "If there is no deal, it's obvious that what will happen is that the European Council will most likely not take place."

Mr Sanchez added that the current "guarantees are not enough and so Spain maintains its veto on the Brexit deal."

"If there's an agreement, we'll obviously go."

Tánaiste Simon Coveney said earlier there may be some room for manoeuvre in the agreement.

"I think you will see Britain and Spain working with Michel Barnier and his team - and indeed other European leaders - to find a resolution to this," he said.

DUP warning

It comes as DUP leader Arlene Foster warned that the deal propping up UK Prime Minister Theresa May's government would be at risk, if the Brexit deal is passed by Westminster.

She told BBC Radio Ulster's Inside Politics: "If she is successful in parliament, and there is no evidence that she is going to be successful in parliament, then of course we will have to revisit the confidence and supply agreement.

"That agreement was about giving national stability, it was acting in the national interest and delivering on Brexit.

"If this is not going to deliver on Brexit then of course that brings us back to the situation of looking at the confidence and supply agreement, but we are not there yet and we are not going to jump ahead until we see what happens in parliament."

Spain has vowed to 'veto Brexit' over the issue of Gibraltar, with Madrid calling for a written UK promise on the peninsula before Sunday's summit.

It is pushing for a say over the future of Gibraltar as a condition for backing a divorce agreement between Britain and the EU.

May's future

Meanwhile Mrs May has repeatedly refused to state whether she would quit if Westminster MPs fail to back her Brexit deal.

In an earlier interview, she said: "I'm focused on actually ensuring we do get this deal through parliament because I believe this is absolutely the right deal for the UK," she said.

Asked twice more if she would quit if parliament rejects her deal, Mrs May added: "As I'm sitting here, I'm not thinking about me.

"I'm thinking about getting a deal through that delivers on the people of this country.

"That's what drives me and that is what is at the forefront of my mind.

"And when I say I'm going to be focused over the next few weeks until the meaningful vote in parliament at getting that vote through, yes I will.

"I'm going to be doing other things too, I'm going to be around the country, I'm going to be explaining the deal to people up and down the country because I think this is important.

"It's not just about the MPs in Westminster looking at the deal, it's about people across the country understanding what the deal is about. So, that's my focus."