The Leeds Central MP claimed Britain’s future in the EU was a “bigger” issue than party politics but made clear he would not be sharing a platform with David Cameron.
Mr Benn said: “We work our separate sides of the street in the course of the campaign.”
He continued: “We’ve got our own Labour campaign and the Conservatives have got their own campaign but in the end everybody who thinks it is in the national interest for Britain to remain in should do everything they can in their own way to encourage people to take that decision when polling day comes.”
Mr Benn insisted Labour leader Jeremy Corbyn is enthusiastically backing the campaign to remain in the European Union despite his Eurosceptic history.
He told Sky News: “He is four square behind Britain remaining in the European Union.
“He is clear, I am clear, the Labour Party is clear. What is this really about? It’s about jobs.”
Mr Benn also expressed surprise at reports London mayor Boris Johnson is set to back the ‘leave’ campaign.
“Boris Johnson in the past has written a lot about the importance of staying in the European Union.
“If he is actually thinking about putting his personal leadership ambitions above the national interest I don’t think it is going to do him any good,” he said.