Donald Trump is proud to still have all his own hair.

The 'Apprentice'host - who is renowned for his distinctive style - has revealed he ignores friends when they advise him to cut off his famous locks because his hair is such an important part of his identity.

In an interview on CNN's 'Piers Morgan Tonight', he said: "I think I am pretty vain. I am. I mean, I think the look is very important. It is my hair. I guess it is [the most famous hair in America]. I can tell you, somebody said why don't you just give yourself a crew cut or shave it or something?

"So it is my hair. And I'll have friends - I had a friend come up to my office recently - I hadn't seen him since high school. He walks up to my office. He weighed 100 pounds too much. He was bald as a - you have no idea, big glasses and a cigar. I said, 'What the hell happened to you?'So it is my hair. I'm very happy."

The business mogul - who has been happily married to Melania Knauss since 2005 - has never had an appetite for alcohol, cigarettes or drugs and instead he admits women have always been his weakness.

Asked if he would give up sex for 10 years in return for $10 billion, he said: "No, I'd absolutely take my wife. Well, I have to say that. I've got to go home. I respect women. I find women very beautiful. I think women are great. I have a fantastic wife, Melania."

Although 64-year-old Donald is set to become a grandfather for the third time when his daughter Ivanka gives birth later this year, he has trouble accepting the title "grandfather".

He explained: "That's a tough word to handle, grandfather. I don't feel like a grandfather, but that's OK. I spoke to a great friend of mine today, Steve Wynn, and he's a grandfather. I said, 'What do you do?'He said, 'I tell them to call me Steve.'He's just a terrific guy. And I said, 'I think I'm going to do that,'let them call me Donald.

'Piers Morgan Tonight'airs daily on CNN at 20.00 GMT.