The House of Commons was forced to debate the motion after a petition on the issue garnered 100,000 signatures, triggering an automatic parliamentary vote.
Mr. Cameron said Britain’s membership in the EU was “vital for millions of jobs and millions of families.” However, 81 Conservatives defied Mr. Cameron’s orders, making it the largest rebellion on Europe since World War II.
Adam Holloway, a lawmaker who resigned from his position as personal private secretary to Europe Minister David Lidington, voted in favor of the motion, saying it is what his constituents want.
“I want decisions to be made more closely by the people affected, by local communities, not upwards toward Brussels,” he said, referring to the Belgian capital that houses most EU operations.
Despite the rebellion, the EU referendum motion was rejected overwhelmingly by a majority of 372.
Ahead of the vote, Mr. Cameron made a strong appeal to members of his party who are disenchanted with the EU. In an attempt to head off a rebellion, he agreed that there is a need for “fundamental reform” of the EU, but he said a referendum on the issue was not the way to achieve this.
“There is a danger that by raising the prospect of a referendum including an in-out option, we miss the real opportunity to further our national interest,” he said.
With an opinion poll showing overwhelming support for a referendum, some Conservative lawmakers said Mr. Cameron will face further rebellions unless he takes a tough stance in EU treaty negotiations in the next year.
Conservative Mark Pritchard said membership of the EU would become “more, rather than less, of an issue” during Mr. Cameron’s next four years in office. He called for “greater clarity” on the government’s plans to bring back powers to Britain that had been conceded to Brussels.
“If we don’t have that clarity, I think the government’s position on Europe is politically unsustainable, given the crisis in the eurozone and indeed possibly a game-changer just coming months down the line in Europe,” he told BBC Radio.
“The Conservative Party will move on from the vote last night, but I do not think Europe, as an issue, is going to move on from this Parliament. It is going to be more, rather than less, of an issue.”
The Liberal Democrats, coalition partners in the Conservative government, and the opposition Labor Party also instructed its members to oppose the motion. Labor leader Ed Miliband said the prospect of a referendum would create further “economic uncertainty.”
“It is not the right thing for Britain,” he said. “It is not the right thing for jobs. It is not the right thing for growth.”