EU referendum: David Cameron to address MPs on deal

David Cameron will face MPs later as he presents his case for the UK remaining within a reformed European Union.

The prime minister will outline details of last week's deal with EU leaders, which paved the way for him to call a referendum on EU membership on 23 June. He says the deal strengthens British sovereignty and the UK will be "safer and stronger" remaining in the EU.

But London mayor Boris Johnson says he will campaign to leave - arguing it is a chance "to vote for real change".

His intervention is being seen as a significant blow to Cameron's campaign to remain in the EU. Johnson, who is also Conservative MP for Uxbridge and South Ruislip, said the referendum was a "once-in-a-lifetime chance" for voters.

In a 2,000-word column for the Daily Telegraph, Johnson said staying inside the union would lead to "an erosion of democracy".

"There is only one way to get the change we need - and that is to vote to go; because all EU history shows that they only really listen to a population when it says no," he wrote.

He added: "This is a moment to be brave, to reach out - not to hug the skirts of Nurse in Brussels, and refer all decisions to someone else. This is the only opportunity we will ever have to show that we care about self-rule. A vote to remain will be taken in Brussels as a green light for more federalism, and for the erosion of democracy."

Several other senior Tories - including Justice Secretary Michael Gove - have already said they will join the Out campaign.

Johnson said one of his reasons for supporting the Out campaign was his concern about the erosion of British sovereignty.

However, his father, Stanley Johnson, told BBC Radio 5 live he disagreed with his son's argument. He denied Johnson's decision had been a "career move", saying he had "completely thrown away" any chance of a post inside Cameron's cabinet by aligning himself against the prime minister.

The Financial Times reports that bosses of about half of Britain's 100 biggest companies are preparing to back Cameron's campaign to keep the country in the union.