The Britain's Got Talent judge described Geldof as a 'sweet and funny girl,' and said that her early death was a 'tragedy.'
'Like I said on the night, I met her, she was a sweet and funny girl. It's a tragedy at that age,' the star told Channel 5 News.
'That whole family, what they've had to go through. I feel really bad for them.'
The new father added:: 'What can you say in a situation like that? Other than every is obviously thinking about them, they need some privacy to get over it in their own time.'
'If it happened to me, I don't know how I would deal with that.'
Yesterday a post-mortem examination proved inconclusive, meaning he family must now wait a further few weeks to receive toxicology results.
In an emotional tribute to his daughter on Monday, Bob Geldof wrote: 'Peaches has died. We are beyond pain. She was the wildest, funnies, cleverest and most bonkers of us all.'
'We loved her and will cherish her forever. How sad that sentence is.'
Peaches leaves behind husband Tom Cohen, and two sons: Astala and Phaedra.