Boris Johnson loses his majority after Conservative MP Philip Lee dramatically crosses floor to join the Liberal Democrats

Reuters

Boris Johnson

Conservative MP Phillip Lee has left his party and joined the Liberal Democrats in a dramatic move which strips Boris Johnson of his majority in parliament.

Lee chose to desert the Conservatives in the most public way possible, crossing the floor while the prime minister was speaking after Parliament returned from summer recess.

Opposition MPs were for a moment quiet before he took his seat next to Jo Swinson, the Liberal Democrat leader before cheers broke out.

Watch Philip Lee cross the floor to join the Liberal Democrats

Lee had been widely touted as a defector for several months and admitted that he was considering joining the Liberal Democrats after calling himself "politically homeless" in the Tory party due to his opposition to Brexit and support for a second EU referendum.

The move means Johnson is now effectively unable to pass any legislation in the House of Commons without the support of opposition MPs, which is rarely forthcoming, and further increases the prospects of a general election, which could be triggered as early as this week.

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