Pedro Sanchez, the Spanish PM, says Spain is now "in a position of strength" in negotiations with the UK over Gibraltar.

Speaking after the summit, he said the withdrawal treaty agreed between the EU and the UK put his country in a position it had not been in previously.

Mr Sanchez had threatened to "veto" the Brexit agreement unless he received a public and written guarantee from Theresa May over the future of the British Overseas Territory.

Gibraltar has been a British territory since 1713, but its sovereignty is disputed by Spain, which wants direct negotiations with the UK post-Brexit.

You can read more about concerns around Gibraltar here.

German Chancellor Angela Merkel says she feels "a certain sense of relief" that a deal has been agreed between the EU and the UK.

The deal balances the interests of both sides, she says, and marks "a very successful endeavour in a difficult situation".

However, there is "still a lot that needs to be done", she warns.

Image source, PA

Nigel Farage has vowed to return to politics if there is a second referendum.

Speaking to the BBC earlier, the former UKIP leader - and focal member of the Leave campaign - described the withdrawal agreement, signed off by 27 remaining EU members on Sunday, as "the worst deal in history".

He said he hoped Parliament would vote the deal down and the UK would "leave on March 29 without a negotiated deal".

He said if the Government failed to pass the withdrawal agreement in Parliament - and the subsequent fall-out led to a second referendum - there was "no question" he would return to politics.

"I haven't spent 25 years battling for this to walk away if we have a second battle."

However he would not commit to rejoining UKIP, amid the furore surrounding the appointment of far-right activist Tommy Robinson as an adviser to leader Gerard Batten.

"We'll have to see what UKIP does," he said.

The prime minister is expected begin a press conference to the media soon.

The EU has ruled out any decision-making role for the UK in EU foreign and defence policy post-Brexit, Irish public broadcaster RTE says.

The UK will be a "third country" once it leaves, with no formal involvement in foreign and defence policy, RTE reports, citing an EU response to concerns raised by Cyprus., external

It's understood Cyprus, as well as Greece, are concerned that any UK access to EU meetings in the area of defence and security would become a precedent and allow Turkey to seek similar access.

Cyprus is wary of any Turkish influence on EU foreign or defence policy. Turkish-occupied northern Cyprus is not internationally recognised.

EU Commission President Juncker warns that "the work is not over" and "the biggest part of the work which is to be done starts now".

"Divorce is a tragic moment, as some of you must know. Payments have to be made. But the future has to be constructed. Britain will not be like other third countries."

He was referring to the close ties forged during UK membership of the EU since 1973.

At the same news conference European Council chief Donald Tusk said it was "impossible for me to predict" the result of the ratification process".

The Brexit withdrawal deal and political declaration still require approval by the UK Parliament and European Parliament if the UK is to leave in an orderly way, as planned, on 29 March.

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Pienaar’s Politics

The DUP deputy leader says the proposition Theresa May has put on the table is "worse than no deal - and worse than staying in the EU".

Speaking on BBC 5 Live, Nigel Dodds says: "The government is going to spend the next fortnight engaged in all sorts of project fear initiatives in order to try to get MPs to vote for something that is clearly unsatisfactory."

The DUP would not be "bought off", he says, adding that "there is absolutely no way this deal can go through on the basis of side offers."

He explained: "We’ve made it clear to the government that our one red line was the fact the UK had to be treated for single market and customs as one entity and unfortunately the government ignored that and decided to go ahead regardless."

One of Britain's biggest business organisations, the British Chambers of Commerce, has called the Brexit agreement "just one more step" on a long road.

Director General Adam Marshall said business was "exhausted by three years of non-stop political debate and growing uncertainty".

Although the agreement was "a milestone" and "a significant personal achievement for the Prime Minister," Mr Marshall said many issues remain unclear.

“If the agreement clears the political hurdles ahead, there can be no pause for breath, and no let-up in the negotiations," he said.

EU chief negotiator Michel Barnier says the deal reached is "fair and balanced".

UK negotiators worked with his team in a "constructive and balanced way", he says, to reach the best deal for both sides.

"We will remain allies, partners and friends", he adds.

Changing to French, he says Brexit "is a very serious situation", with the deal giving "legal certainty to all those affected by the uncertainty created".

EU Commission President Jean-Claude Juncker says: This is the best deal possible for Britain, this is the best deal possible for Europe, this is the only deal possible."

He spoke in English, in a message to UK politicians, urging them to accept the deal.

He also sought to reassure Britons working for the EU in Brussels.

He called it "a good deal, a sad deal".

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Asked whether the government could collapse in the next few weeks if it cannot get the Brexit deal through the House of Commons, Foreign Secretary Jeremy Hunt said "it's not possible to rule out anything".

However, he remained optimistic - "we are going to get through this".

European Council President Donald Tusk says "one thing is certain – we'll remain friends until the end of days and one day longer".

He is speaking at a joint news conference with EU Commission President Jean-Claude Juncker.

Mr Juncker says "it’s a very sad day". The EU leaders, he says, "all attempted to express their sadness - it was broadly shared, if not unanimously shared".

Image source, BBC News

Jean-Claude Juncker, Donald Tusk and Michel Barnier are now holding a media conference after EU leaders agreed to back the Withdrawal Agreement and Political Declaration.