EU referendum: Jeremy Clarkson and James May say Brexit would hurt The Grand Tour

Former Top Gear stars Jeremy Clarkson and James May have joined forces and backed a Remain vote at the EU referendum. The presenters, who are best known for their motoring rivalry, argued that a Brexit at the 23 June vote would have a detrimental impact on their new Amazon Prime show, The Grand Tour.

"It annoys me actually, I'll be honest, because I want to Remain in Europe but that means agreeing with him," Clarkson joked. May added: "Yeah, this is very uncharacteristic. We've had to put aside the normal policy of our TV show and our relationship and agree on something apart from 'the Ford Mondeo is a good car'."

Clarkson warned that outside of the 28-nation bloc, The Grand Tour team would face troubles testing cars on the continent. "If we weren't in Europe we'd have to get a carnet made every single time we wanted to go to one of these [EU] countries and that would take well, a hundred years," he claimed.

The video comes after numerous celebrities have come out for either Remain or Leave. Actor Sir Michael Caine branded the EU as a "government by proxy over everybody, who has now got carried away. Unless there's some extremely significant changes, we should get out," he told BBC Radio 4's Today Programme in February.

The EU referendum campaigns have also used endorsements from high-profile business people, such as inventor and Brexit backer Sir James Dyson and serial entrepreneur Sir Richard Branson, who is supporting Remain.

With just days to go before the 23 June vote, the latest opinion polls have showed a swing towards Remain. A telephone survey from Survation, of more than 1,000 people between 17 and 18 June, put Remain on 45% and Leave on 42%. A separate online poll from YouGov, of more than 1,600 people between 16 and 17 June, put Remain on 44% and Leave on 43%.