LONDON --  Prime Minister David Cameron takes a deal giving Britain "special status" in the EU back to London on Saturday hoping it will be enough to keep his country in the bloc as campaigning begins for a crucial in-out referendum.

   The British premier is expected to announce a date for the vote, likely June 23, after sealing unanimous support for the agreement during two days and nights of intense negotiations in Brussels.

   Cameron will hold a cabinet meeting at 1000 GMT on Saturday, after which the referendum campaign will whirr into life, with ministers who want Britain to leave the European Union being allowed to speak out for the first time.

   "I've negotiated a deal to give the UK special status in the European Union," Cameron told a press conference on Friday evening.

   "I will be campaigning with all my heart and soul to persuade the British people to remain in the reformed European Union that we have secured today."

   He said the deal contained a seven-year "emergency brake" on welfare payments for EU migrants and meant Britain would be "permanently out of ever closer union".

   While Britain's place in the EU now rests in the hands of the British public, the deal relieves some of the pressure on Brussels as it grapples with the biggest migration crisis in Europe's history.

   EU president Donald Tusk, who brokered the agreement, said the "unanimous" deal "strengthens Britain's special status in the EU" and was "legally binding and irreversible".

   - 'Depressingly negative campaign' -

   German Chancellor Angela Merkel, Europe's most powerful leader, said the accord was a "fair compromise".

   "I do not think that we gave too much to Great Britain," she said.

   French President Francois Hollande insisted the deal contained "no exceptions to the rules" of the EU, but Italian Prime Minister Matteo Renzi warned "there is a risk of us losing sight of the original European dream".

   The euro and British pound gained after the announcement, with the single currency rising to $1.1131 in New York, from $1.1105 Thursday, and the pound to$1.4392 from $1.4335.

   Yet the drama is only just beginning for Cameron, as he battles eurosceptic members of his own Conservative Party and scepticism  within the British media.

   Britain's newspapers went to press shortly before the deal was officially announced, and most of Saturday's editions focussed on the expected announcement that Cameron's long-time ally Michael Gove was to support a "Brexit".

   The Guardian, Daily Telegraph, and Independent all carried front-page pictures of the former education secretary, while the eurosceptic Daily Express ran with headline: "Gove to lead us out of EU."

   Opinion polls suggest the British public is finely balanced on whether to back a Brexit.

   Anand Menon, professor of European politics at King's College London, said he expected both sides to emphasise the risks of either leaving or sticking with the status quo.

   "This is going to be a depressingly negative campaign," he told AFP.

   - Headaches at home -

   During negotiations, France and Belgium strongly resisted safeguards for countries that do not use the euro. European Commission chief Jean-Claude Juncker said the deal would give Britain no power of veto over the eurozone.

   Britain and other "euro-outs" will, however, be able to raise concerns about eurozone policies at the level of EU summits.

   Meanwhile, Eastern European countries dug in their heels over restrictions on benefit payments to EU migrants that they deemed discriminatory and in violation of the bloc's principle of freedom of movement.

   Brussels offered an "emergency brake" which would allow Britain to limit welfare payments if its system is overwhelmed by the inflow of workers.

   Cameron now faces fresh political headaches at home as key allies, including London Mayor Boris Johnson, make up their minds whether to back the prime minister or throw in their lot with the 'No' camp.

   On Monday, his government is expected to table measures in the Houses of Parliament to set the date for the vote.

   This will be Britain's second referendum on European membership in just over 30 years.

   In June 1975, voters backed membership of the then European Economic Community (EEC) by just over 67 percent. (AFP)