Sharon Osbourne teamed up with the property tycoon when he fronted hit U.S. reality TV competition show Celebrity Apprentice, and she admits she found Trump to be an "absolute gentleman" - but she fears his narcissism will trip him up as a leader.

Appearing on U.S. late night show Conan on Tuesday (22Sep15), she explained, "Working with him... he was very respectful, very nice, but... when you watch him on the (political) debates, it just reminds me of a three-hour episode of The Apprentice. (He's) acting the same way (as he does on the show) - the wisecracks, the one-liners... It's like, 'You're not meant to act that way. It's serious. Come on!'

"He's rolling the dice (by becoming a candidate). If by some chance he does make it (to the White House), fantastic, if he doesn't he's built his empire even bigger... He can't lose really."

Trump has captured the imaginations and support of many Americans and he is currently leading the race to be named the Republican Party's candidate for President when the nation goes to the polls next year (16).

But Osbourne fears a vote for Trump will be a bad one, adding, "I would be terrified because he's a narcissist... and he doesn't take comment well and if anybody disagrees with him, he doesn't take it well. And to think that this man would have his hand on that button, can you imagine? He's got such a quick fiery temper... He could never be in a position like that."