Lord Sugar - the Government's newly appointed Enterprise Tsar - has warned the Remain campaign must do a better job of explaining why Britain needs to stay in the EU.
The Apprentice boss, who is launching a drive to encourage young people to set up their own businesses, said it would be "crazy" for Britain to leave the 28-nation bloc.
He expressed concern however that voters were being confused by the exaggerated claims being made by both sides in the referendum.
"I'm very concerned about this because ordinary people that I speak to are very, very confused," he said in an interview with BBC2's Newsnight.
"They are not stupid and they know they are being frightened by the Brexit people and frightened by the staying in people."
In particular he expressed concern that the Remain campaign needed to do more to substantiate its claims about the consequences of a vote for Brexit.
"I said to the Prime Minister the other day you have a whole host of people giving you a load of statistics which you are rattling off," he said.
"If it was me I would say 'give me the detail so that I can tell ordinary people that I'm not just going to say things like jobs will go', I will want to explain why jobs are going to go? That's got to happen in the next two weeks."
Lord Sugar's recruitment as Enterprise Tsar was hailed as a coup for the Government after he was originally made a Labour peer by Gordon Brown only to quit the party last year saying it had moved too far to the left.
In the interview, he delivered a stinging sideswipe at Boris Johnson, dismissing him as "an ex-mayor who has gone off the rails".
"I had a lot of respect for him until a couple of weeks ago with some of the outlandish things he has been saying," he said.
He also renewed his old rivalry with Donald Trump, the US presidential hopeful, and his counterpart on the American version of The Apprentice.
"If I was an American I would be very, very worried," he said. "Mr Trump considers himself a great businessman...I've been in business for 50 years...I haven't put any companies I've been involved in into insolvency or anything like that."