Parts of the Leave campaign contesting the referendum on British membership of the EU to be held next month are "based on prejudice", former Labour leader Ed Miliband has warned.
Mr Miliband launched the attack as he expressed fears that a failure by young people to register to vote could hand the Brexit camp an accidental victory.
"I think you see elements from the Leave campaign based on prejudice. When Nigel Farage says on television to Peter Mandelson 'you are rubbing our noses in diversity', I think that's an offensive remark," Mr Miliband said at a Remain push in north London aimed at encouraging young voters to turn out.
The intervention came as Tory in-fighting escalated with pro-Brexit employment minister Priti Patel launching a scathing attack on the "chaos" of Britain's immigration controls, as she ridiculed economic predictions from Government colleagues in the Treasury.
Mr Miliband insisted that immigration was good for Britain, and the “flip side” was that young British people could travel and work freely across the EU.
Asked about concerns mass migration was pushing down wages, Mr Miliband said: "We would do far, far more damage to people on lower incomes by leaving the European Union. Economically we would do damage.
The loss of workers’ rights will do damage.”
The ex-Labour leader warned that 1.5 million of the six million 18-24-year-olds eligible to vote are not registered, nor are a quarter of the eight million 25-35-year-olds.
“Today is a call to arms to all young people to register to vote. Let’s be clear about the danger: a decision not to vote is a decision to let someone else decide your future.
“Young people can decide this referendum. If they don’t use their vote, the danger is this referendum will be lost,” Mr Miliband said.
Mr Miliband took questions from young voters at the event, and also a question on the EU's impact on fish markets from reality TV star Joey Essex.
Mr Miliband's comments on prejudice and wages helped put immigration back at the centre of the debate as Ms Patel launched a thinly-veiled swipe at pro-Remain Home Secretary Theresa May.
Ms Patel wrote in The Sun: “There is another great bonus of leaving the EU, we’ll be able to design a new immigration system that brings the chaos under control and helps the economy.
“It’s uncontrolled and uncontrollable while we remain in the EU. If the Government seriously believed the doom-laden propaganda they have been pumping out about the horrors of life after the EU, they would never have called this referendum in the first place.
“The Government thinks it can predict what will happen in the economy in 2030. Last November, the Treasury said there was going to be a windfall of £27 billion from unexpectedly high tax receipts.
“When the Budget came round in March, that had turned into a £56 billion shortfall. Fourteen years ahead? They can’t even predict 14 weeks ahead.”
The move came as Mr Cameron said he would not reconsider comments that Boris Johnson, George Osborne and Mrs May were all figures who could step into his shoes when he steps down, as he has promised he will before the next general election.
The prime minister said: “I wouldn’t withdraw any of the things I’ve said. The Conservative Party is lucky to have big substantial figures within it and that’s certainly the case. But on this one, I think he is on the wrong side.”