Jeremy Corbyn has ruled out ever sharing a stage with Prime Minister David Cameron on Europe, saying the two have "opposite" agendas.
Both Mr Corbyn and Mr Cameron are campaigning for Britain to remain in the EU, but the two have different views on what the Union should look like.
Speaking on ITV's The Agenda, the Labour leader, criticsed Mr Cameron's vision of a "free market Europe".
Asked if he could ever see himself supporting Mr Cameron on EU membership, given that they both believe the UK should remain in the Union, he replied:
Helena Morrissey, CEO of Newton Investment Management, who was also on the show, said while she appluded Mr Corbyn's vision it seemed an unlikely direction for the EU to take.
"I would love to see what Jeremy is setting out but I think it is fantasy," she said.
On leaving Europe she added: "There is uncertainty if we stay or if we go. I'm not arguing for a slamming of the door and flouncing out but for a conscious uncoupling."
Also on The Agenda tonight: