David Cameron has vented his frustration at Boris Johnson over Europe, as he ridiculed the mayor of London over his apparent call for a second EU referendum and came close to accusing him of backing a vote to leave to boost his chances of one day leading the Conservative party.

In a sign that a Tory truce on Europe is under severe strain before the official campaigning has even begun, the prime minister infuriated anti-EU campaigners by describing Johnson’s idea for a second vote as undemocratic and one “for the birds”.

As the London mayor shook his head and shouted “rubbish” in the Commons chamber, the prime minister mocked Johnson by likening his idea for a second referendum to a couple who start divorce proceedings as a way to make up.

“I have known a number of couples who have begun divorce proceedings,” Cameron said in remarks that were seen to be aimed at Johnson, who has experienced trouble in his marriage. “But I do not know any who have begun divorce proceedings in order to renew their marriage vows.”

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Senior Tories say that the prime minister decided to turn his fire on Johnson because he felt the London mayor had misled Downing Street over which side he would support in the referendum. As recently as a week ago the London mayor told one senior Tory who is helping the prime minister to prepare for the referendum campaign: “I’m sure I will be with you.”

The prime minister held back his most politically stinging remarks to the end of his prepared statement on the EU deal when he spoke of how his decision to stand down as prime minister by 2020 showed he was motivated solely by protecting the national interest.

In comments that appeared designed to highlight the apparently personal calculations behind Johnson’s approach to the referendum, the prime minister said: “I am not standing for re-election. I have no other agenda than what is best for our country.

“I am standing here today telling you what I think. My responsibility as prime minister is to speak plainly about what I believe is right for our country.”

Friends of the London mayor said he was not bothered by the prime minister’s remarks and had not noticed some of the jibes. One friend said: “C’est la vie. Boris was not remotely angry or bothered. He noticed the joke about the second vote. But he didn’t notice the joke about marriage or the [leadership] election.”

But a handful of Tory MPs later challenged the prime minister at a meeting of the backbench 1922 committee. Steve Baker, the Tory MP for Wycombe, who is a leading member of the Vote Leave group, told the prime minister: “I know how hard it is. But please be kind to Boris.”

Facebook Twitter Pinterest David Cameron and Boris Johnson in the House of Commons. Composite: Parliament TV

The prime minister reportedly assured the MPs that he would be kind and respectful towards Tories who want to take Britain out of the EU. As he left the meeting the prime minister hugged the arch-Eurosceptic MP Philip Davies and said: “It is love breaking out.”

Baker said: “Boris has had quite a beating in the press. It was bruising for him in the Commons. This shows Boris has done this out of personal conviction because he is paying a price.”

Cameron’s attack on Johnson came as he delivered a Commons statement on the outcome of last week’s European council where he succeeded in renegotiating the terms of the UK’s EU membership after a marathon round of talks.

Replying to the prime minister’s statement, the Labour leader, Jeremy Corbyn, described Cameron’s deal as “largely irrelevant”, saying it would have no impact on the case to remain in the EU.

The prime minister also published a white paper outlining his reform plans, which include a seven-year emergency brake to restrict in-work benefits for EU migrants. The white paper prompted claims that the government was reviving the “Project Fear” tactics of the Scottish referendum. In a foreword to the 43-page document, Cameron wrote: “Leaving Europe would threaten our economic and our national security.”



Downing Street also published secondary legislation to set the ground rules for the referendum. This will formally set the date for 23 June and will allow the Electoral Commission to open the process to designate lead campaigns on both sides on 4 March with a deadline for completion on 1 April. The formal campaign will begin on 15 April.



Cameron’s assault on Johnson came after the London mayor announced on Sunday that “after a huge amount of heartache” he would support a leave vote. In his weekly Daily Telegraph column, Johnson appeared to revive his support for a second referendum on Britain’s relationship with the EU even if the UK voted to leave.

The suggestion by the London mayor shows the influence of Dominic Cummings, the Vote Leave campaign director and former special adviser to Michael Gove, who has suggested that Cameron should use a leave vote to demand better terms from the EU.

Cummings believes the prime minister should hold his nerve if he loses the referendum and refrain from invoking article 50 of the Lisbon Treaty, which would trigger two years of exit negotiations. This would be designed to put pressure on EU leaders to negotiate a new “grand bargain” between Britain and the EU.

The prime minister moved to quash the idea by indicating that he would invoke article 50 “straight away”, thereby triggering a two-year negotiation on a take-it-or-leave-it exit package. Cameron’s remarks suggests he would act on Friday 24 June, the day after the referendum, when EU leaders are due to conclude their annual mid-summer summit.



Cameron’s position was backed by senior officials in Brussels, who emphasised that “no means no” in the referendum in June and that a rejection of EU membership by the British would trigger further negotiations, but only on the terms of the split.

Mocking Johnson, the prime minister said: “I won’t dwell on the irony that some people who want to vote to leave apparently want to use a leave vote to remain. Having a second renegotiation followed by a second referendum is not on the ballot paper.

“And for a prime minister to ignore the express will of the British people to leave the EU would not just be wrong, it would be undemocratic. On the diplomacy, the idea that other European countries would be ready to start a second negotiation is for the birds.”



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Downing Street said that the white paper, titled The Best of Both Worlds – Our Special Status in a Reformed EU, illustrated the impact of the welfare reforms that will curb access to in-work benefits for EU migrants. It said that of the £25bn spent on in-work benefits in the UK in 2013-14, £2.5bn went to migrants from the European Economic Area.



But the document also paved the way for a potentially controversial change to the rules on social housing, which will mean that new tenants trying to get council and other social housing will be required to live in the local area for four years instead of the current two. The white paper makes clear that the change in the “residency test” will not just apply to new migrants but also anyone moving within Britain.

“This is aimed at ensuring that sufficient affordable housing is available to those amongst the local population who are on low incomes or otherwise disadvantaged and who would find it particularly difficult to find a home on the open market. We will extend this period to four years.”

The Foreign Office paper says that existing official guidance to local authorities in England already makes clear that they should require a potential tenant to live in the area for at least two years before they are considered for social housing.

Additional reporting by Ian Traynor