She first become agitated when the journalist suggested she had been eclipsed by her best friend turned rival, Kim Kardashian. He asked: 'Do you worry at times that people who have followed in your footsteps like Kim Kardashian are over shadowing you?'
Through gritted teeth, she replied: 'No, not at all.'
She became even more irritated when mentioned that her latest reality TV show The World According to Paris has struggled in the ratings.
The journalist continued: 'Do you worry about your moment being past?'
Hilton, 30, glanced across at someone off camera before getting up from her chair and stormed out. She could be heard saying off camera: 'I don't want all this being used.'
After a 'heated' discussion between Harris, Hilton and her publicists, she eventually returned to camera to deliver an apparently well-rehearsed answer.
'I've been doing this for 15 years now, so it's been a long time so just like any other business person or someone in the industry, it is always important to reinvent yourself and come up with new projects,' she said.
Before that Hilton had been happy to discuss her changing career.
'So many people that are rich do nothing.
'I like being able to do what I want, to buy whatever I want, and to not ask for permission like some of my other friends who are adults but live like children.'
Hilton was also asked about the alleged stalker arrested outside her home on July 4.
'It is very unsettling, because you don't know what frame of mind someone like that is in.
'Now four times he has tried to get in contact with me.
'He's keeps getting in trouble for it, yet he keeps coming back, so obviously there's something wrong with him.'