LONDON -- Prime Minister David Cameron, who canceled a long-anticipated speech because of a hostage crisis in Algeria involving Britons, planned to deliver an explicit warning that Britain might leave the European Union if changes in its administration were not made, according to excerpts from the speech released Thursday and embargoed until Friday.
According to the excerpts, Mr. Cameron would have said that without changes in the European Union, "the danger is that Europe will fail and the British people will drift toward the exit" -- a statement that drew an admonition from President Obama telling Britain not to jeopardize its membership in the European Union, British newspapers reported.
On Thursday, Mr. Cameron canceled his speech, which was to have been delivered Friday in Amsterdam, citing the need to stay in London to be on hand for developments in the hostage crisis in Algeria, where Britons were among the dozens of captives taken by Islamic militants at a natural gas plant operated partly by BP, the British-based oil giant. In Amsterdam, Mr. Cameron had planned to set out an outline of a plan to renegotiate a pared-down role for Britain in the 27-nation European Union, rebuffing the centralizing momentum in other major European nations as they struggle to save the euro, the common currency that Britain has shunned, and to call a referendum by 2018 on the result.
In advance of the speech, Mr. Cameron placed calls Thursday to Mr. Obama and President François Hollande of France to set out what he would say, British officials said.
A White House spokesman said Mr. Obama "underscored our close alliance with the United Kingdom and said that the United States values a strong U.K. in a strong European Union, which makes critical contributions to peace, prosperity and security in Europe and around the world."
The warning came a week after a senior State Department official, Philip Gordon, the assistant secretary for European affairs, said a continued "strong British voice" in an "outward looking" European Union was in America's interests, and warned specifically against the referendum on Europe, which is an important component in Mr. Cameron's plans. "Referendums," Mr. Gordon said, "have often turned countries inward."
In the excerpts, Mr. Cameron planned to warn that there was "a gap between the E.U. and its citizens which has grown dramatically in recent years and which represents a lack of democratic accountability and consent that is -- yes -- felt particularly acutely in Britain."
"If we don't address these challenges, the danger is that Europe will fail and the British people will drift toward the exit," Mr. Cameron planned to say. "I do not want that to happen. I want the European Union to be a success, and I want a relationship between Britain and the E.U. that keeps us in it."
"People are increasingly frustrated that decisions taken further and further away from them mean their living standards are slashed through enforced austerity or their taxes are used to bail out governments on the other side of the Continent," he was to say, according to the excerpts.
"And yes, of course, we are seeing this frustration with the E.U. very dramatically in Britain," the excerpts said. "Europe's leaders have a duty to hear these concerns. And we have a duty to act on them."
But according to the news agency Press Association in Britain, which published the excerpts, they did not reveal whether he intended to commit himself to a referendum offering Britons a yes-or-no response to continued membership.
John F. Burns reported from London and Alan Cowell from Paris.
This article originally appeared in The New York Times.