The government should delay triggering Article 50 – the two-year process for formally quitting the bloc – “for as long as it takes to get an idea of how the other side looks”, according to the former prime minister.
A downturn in economic fortunes could lead to a change in attitudes about the country’s future outside the EU, he suggested.
“One of the reasons why we should keep our options open is that, yes, the referendum expressed the will of the people, but the will of the people is entitled to change,” he said.
“Over the next two months, even while this psycho drama within the Conservative Party is going on, we’ve got to have the national interest protected by trying to set the scene for any negotiation.”
He added: “I don’t think you can override the settled will of the people, but it’s 52 to 48. Supposing some weeks or months down the line, as it becomes clear what we are moving to, as that becomes clear, if it becomes clear these terms are bad for us, if people start to worry about their jobs, we should just keep our options open.”
He added: “I’m simply saying there’s no rule about this – we’re a sovereign people, we can do what we want to do.”