David Cameron Rules Out Third Term as Prime Minister of Britain

Just over six weeks before seeking a second term in May’s general election, Prime Minister David Cameron of Britain has ruled out serving a third, in a declaration that provoked surprise as well as criticism and put his Conservative Party on the defensive.

In a wide-ranging interview with the BBC on Monday, Mr. Cameron said he would run for a full second term but added, “The third term is not something I am contemplating,” a stance that could undermine his authority if he secures an election victory on May 7.

Likening prime ministerial terms to portions of a breakfast cereal, Mr. Cameron said they were “like Shredded Wheat: two are wonderful but three might just be too many.”

He even went on to name potential successors, like Theresa May, the home secretary; George Osborne, the chancellor of the Exchequer; and Boris Johnson, the mayor of London.

There is no limit in Britain on the number of terms a prime minister can serve, and the issue occasionally raises problems for leaders who discuss their long-term ambitions. Former Prime Minister Margaret Thatcher once famously courted controversy by saying that she would go “on and on.” She was ultimately deposed by members of her own party in 1990.

James Landale, the deputy political editor of BBC News, who conducted the interview with Mr. Cameron, later wrote that his intention appeared to be to “get across the message” that he would serve a full five-year term if he won in May and that he would not step down midway through it.

There has been speculation that a victorious Mr. Cameron would quit after holding a referendum on whether Britain should remain in the European Union. Mr. Cameron has promised a referendum on that issue by the end of 2017.

If putting an end to such speculation was the intention, the comments appeared to have backfired. In a statement issued Monday, Douglas Alexander, the head of general election strategy for the opposition Labour Party, accused the Conservatives of “taking the British public for granted.”

“It is typically arrogant of David Cameron to presume a third Tory term in 2020 before the British public have been given the chance to have their say in this election,” the statement said.

The junior coalition party, the Liberal Democrats, also issued a statement describing the comments as “incredibly presumptuous.”

The comments stirred speculation about leadership battles in the Conservative Party, and reaction from the news media was largely negative, including among Conservative-leaning newspapers. The Daily Mail said Mr. Cameron “risked undermining his prime ministerial authority,” and The Sun remarked, “The admission was seen as a big gaffe.”

Television and radio news shows debated whether the declaration meant that Mr. Cameron would resign well before the election scheduled for 2020, to allow a successor to establish a footing, or continue as prime minister until the day of the election.

But the prime minister’s allies defended him. The defense secretary, Michael Fallon, described Mr. Cameron’s comment as “a fairly straight answer” and “a fairly obvious answer.”

“There is a shelf life to any politician,” Mr. Fallon told the BBC. “Nobody is absolutely indispensable.”

Tony Blair’s final election victory, in 2005, was overshadowed by tensions with his eventual successor, Gordon Brown, over when Mr. Blair would quit. He eventually did so in 2007, after 10 years in power.

As for why Mr. Cameron entered this treacherous political territory at such a delicate time, Mr. Landale wrote that it appeared to be a spontaneous, rather than scripted, response.

“I asked him a question, and he answered it,” Mr. Landale wrote. “It was just one of many speculative questions that political journalists like me ask in the hope that, just occasionally, they might get an answer. And this time it did.”