Britain will hold a referendum on its membership in the European Union in June, a vote that Prime Minister David Camerson said would be "one of the biggest decisions this country will face in our lifetimes."
Cameron made the announcement February 20 a day after the conclusion of protracted negotiations in Brussels with leaders of the 28-member bloc.
The June 23 vote will come at a critical moment for the bloc, which is grappling with the influx of refugees from the Middle East and North Africa and stagnant economic growth.
Britons have historically been the least enthusiastic members of the bloc, and Britain has retained its own currency, rather than the euro, along with other exemptions.
They include allowing Britain to curb immigration while safeguarding the country’s powerful financial center from heavy euro-zone regulation.
After a rare Cabinet meeting on February 20 Cameron said his ministers had approved a government position recommending Britain stay in a reformed EU.
"Britain will never be part of a European superstate," Cameron said. "We have never liked it, we have never wanted it."
"We will be out of the parts of Europe that don't work for us, and in the parts that do -- the best of both worlds," Cameron said.
German Chancellor Angela Merkel, who was determined to keep Britain in the bloc, called the deal a "fair compromise," and said, "I do not think we gave too much to Great Britain."
"We have sent out a signal that we are all willing to sacrifice part of our interests for the common good," said EU President Donald Tusk, who led the negotiations.
Cameron's Conservative Party has been split by the issue, and though Cameron himself will campaign to keep Britain in the EU, at least one of his Cabinet minister has said he will campaign against that choice.