Former Ukip leader Nigel Farage has attacked the “deeply worrying” failure of EU exit talks to address border controls after a meeting with Brussels’ chief Brexit negotiator.

Michel Barnier does not understand at all that immigration fuelled the vote to leave and believes the result was down to the promise of extra cash for the NHS, the former Ukip leader said.

Mr Farage also warned that businesses will push for the Government to walk away from talks if the EU fails to make any concessions on financial services.

He said: “What he really didn’t understand at all was that open door immigration within the EU had been an absolute key driver of all of this.

“He really doesn’t see that. The most disappointing thing, if I am speaking on behalf of the 17.4 million, most of them anyway, is that it’s pretty clear that in the talks that have happened so far immigration, frankly, hasn’t even been discussed.

“We haven’t even begun to talk about how we are going to put some proper controls in place.”

Mr Farage said it was clear that the Government has not yet discussed border controls with Mr Barnier, which is “deeply worrying for Brexiters”.