London's mayor Boris Johnson threw his considerable influence behind the push for a British exit from the European Union on Sunday, Feb. 21. (Reuters)

London's mayor Boris Johnson threw his considerable influence behind the push for a British exit from the European Union on Sunday, Feb. 21. (Reuters)

A day after London Mayor Boris Johnson threw a bombshell into British politics by backing a British exit from the European Union, the financial world felt the ricochet Monday as the pound plunged in value.

The British currency experienced a more than 2 percent drop against the dollar, reaching its lowest level in nearly seven years. The sell-off of the pound sterling came as markets reacted to a move that analysts say has raised the odds that Britain will vote to leave the 28-member club when the country votes in a June referendum.

[Boris Johnson backs ‘Brexit,’ boosting anti-E.U. campaign]

“Sterling seems to have fallen off the Boris cliff this morning,” wrote Ranko Berich, head of market analysis at Monex Europe, in a briefing note. “This could be just the start of the great Brexit Selloff of 2016.”

The market turmoil reflected a broader apprehension that Britain could be veering toward an E.U. departure.

The British pound sank against the dollar as the defection of London Mayor Boris Johnson to the "Brexit" camp adds to concerns that a British departure from the European Union is a real risk. (Reuters)

The country is due to vote June 23, and polls have shown the two sides to be virtually tied.

But those surveys were conducted before Johnson, London’s raffish mayor, broke with expectations and announced Sunday that he would defy British Prime Minister David Cameron by backing the campaign for a British exit, or Brexit. The decision instantly gave the “out” campaign a charismatic champion and raised the stakes of the vote.

It also seemed to infuriate Cameron, who was barely able to hide his contempt over the defection during a heated debate in the House of Commons on Monday. At one point, he seemed to be questioning Johnson’s motives for backing Brexit.

“I am not standing for reelection, I have no other agenda than what is best for our country,” Cameron said.

Johnson made his case for Brexit in an article on Monday in the Daily Telegraph, where he depicted the European Union as an ­out-of-control bureaucracy that was eroding British sovereignty and preventing the public from kicking out “the men and women who control their lives.”

“We are seeing an alienation of the people from the power they should hold, and I am sure this is contributing to the sense of disengagement, the apathy, the view that politicians are ‘all the same,’ ” he wrote.

[What’s a ‘Brexit’? ]

British Prime Minister David Cameron rules out a second referendum on Britain's E.U. membership saying, "I won't dwell on the irony that some people...want to use a leave vote to remain" (Reuters)

If Britain chooses to leave the European bloc, Cameron is likely to come under intense pressure to resign. And Johnson, a fellow Conservative whose popularity far exceeds that of the strait-laced prime minister, would be well positioned to take Cameron’s place.

Speaking to the BBC on Monday, Johnson’s father, Stanley Johnson, denied that his son had made his choice based on political opportunism. It could, said the elder Johnson, be “a career-ending move.”

But it could also be a career-maker — while carrying Britain out of Europe in the process.

[Europe wants Britain to stay in the E.U., but not at any cost]

On Monday afternoon, Cameron laid out his case for backing the “in” campaign during his first address to Parliament since he set the referendum date, at times having to shout to be heard above the din.

Although he didn’t mention Johnson by name, he was clearly referring to him when he said the U.K. would not have a second E.U. referendum if it voted to “leave” in June.

Some people favor voting to “leave” as a way to pressure the E.U. into giving Britain a better deal. Johnson appeared to suggest this idea in his Daily Telegraph column.

“I have known a number of couples who have begun divorce proceedings, but I do not know of any who have begun divorce proceedings in order to renew their marriage vows,” Cameron said in one of his swipes.

A second referendum was “not on the ballot paper,” he insisted.

Political analysts were watching the debate closely for clues on who was lining up on what team, with some suggesting around half of Conservative Party members of Parliament could end up backing Brexit.

By contrast, the opposition Labour Party — my “new friends,” Cameron called them — is relatively united in favor of membership.

Its leader, Jeremy Corbyn, dismissed Cameron’s E.U. renegotiations as a “theatrical sideshow,” but told Parliament that the Labour Party was “overwhelming for staying in.”

When it finally came time for Johnson to ask a question — as he stood up, an MP shouted, “Tuck your shirt in, Boris” — the mayor pressed Cameron on how the E.U. deal returned sovereignty to the U.K. Johnson seemed unimpressed with Cameron’s answer, muttering “rubbish” in response.

Until Johnson’s announcement Sunday, the main advocates for “out” were primarily fringe players in British politics.

But the mayor — who has won fans with his bumbling affability — is “the one figure who the political classes calculate could remove the fear factor from the idea of Brexit for the wider U.K. population,” according to Mujtaba Rahman, lead Europe analyst for the Eurasia Group.

In a briefing note, Rahman laid out what he called “the doomsday scenario for Cameron,” in which “the Boris move causes contagion” among the Tory rank-and-file, with hundreds of defections from the Conservative ranks in Parliament.

But he concluded that is unlikely.

“Despite this calamitous weekend for Cameron,” Rahman wrote, “we believe Downing Street will be able to regain control of the debate in coming weeks as it relentlessly refers to the U.K.’s new arrangement as ‘the best of both worlds.’ ”

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