British Prime Minister David Cameron announced on Saturday he would hold a referendum on Britain's membership of the European Union on June 23.
He said "I will go to parliament and propose that the British people decide our future in Europe through an in-out referendum on Europe on Thursday the 23rd of June. My recommendation is clear. I believe that Britain will be safer and stronger and better off in a reformed European Union."
Cameron also said the cabinet had approved a government position recommending Britain stay in a reformed EU.
Hoowever, one of Cameron's closest political allies, Justice Secretary Michael Gove, and five other cabinet members opposed the deal and said they would campaign to leave. They signed a poster for the "Vote Leave" campaign saying "Let's take back control."
"The EU is an institution rooted in the past," Gove said, adding that Britain had exported a democratic system of self-government to nations like the United States, India, Canada and Australia that had brought prosperity and peace to millions.
"Our country would be freer, fairer and better off outside the EU," he said.
While a rebellion by 6 out of 30 cabinet members illustrated the depth of the party's split over Europe, Cameron's most senior ministers including interior minister Theresa May and finance minister George Osborne backed EU membership.
Opinion polls suggest the British public is finely balanced on whether to back a Brexit or not.
'Special status' for Britain
British Prime Minister David Cameron had said on Friday that European Union reached a reform deal that would give Britain "special status" in the bloc.
"I have negotiated a deal to give the UK special status in the EU. I will be recommending it to Cabinet tomorrow," Cameron said on Twitter.
European Council President Donald Tusk said an agreement to keep Britain in the bloc won unanimous support from all of the EU states 28 leaders.
Cameron said he would campaign with all his "heart and soul" for Britain to stay in the European Union.
At a news conference, Cameron said the deal had delivered what he promised British voters when running for his second term and would recommend the agreement to his cabinet on Saturday. He said he would set a date for a referendum soon.
"The British people must now decide whether to stay in this reformed European Union or to leave. This will be a once in a generation moment to shape the destiny of our country," he said.
"I believe that this is enough to recommend that the UK remain in the EU having the best of both worlds."
The British prime minister also said he would offer new proposals to strengthen the country's sovereignty - a clear bid to try to keep the more sceptical lawmakers in his Conservative Party on board with his campaign to keep Britain in the bloc.
The deal was reached late on Friday after the EU's two top figures, Donald Tuskand Jean-Claude Juncker, presented its 28 leaders with draft proposals at a long-delayed dinner.
It came after France, Belgium and eastern European countries dug in their heels over changes to areas including regulation for non-eurozone countries and benefit payments to EU migrants for four years.
Cameron said Britain would now be "permanently out of ever closer union", one of the EU's founding principles, while Britain would be able to apply "tough new restrictions on access to welfare."
European leaders have agreed on a "fair compromise" deal with Cameron, with which he can campaign to keep Britain in the bloc, German Chancellor Angela Merkel said at the conclusion of an EU summit.
"We believe that with this we have given David Cameron a package with which he can campaign in Britain for Britain to stay in the European Union," Merkel told reporters at the end of the two-day summit.