Robbie Williams hates his hairy butt cheeks.

The 'Party Like A Russian' singer says as he's gotten older the follicles on his bum have grown thicker and longer and he has become a ''hairy dad''.

Robbie was told by his stylist that the trouser area hair could be removed with a good ''cut-throat'' razor but he can't reach around to his fuzzy peach and he is loathed to make his wife Ayda Field shear his rear so he opted for a crack wax which he is no hurry to repeat due to the pain involved.

In an interview with The Daily Telegraph Australia, he over-shared: ''I'm a hairy dad. I can't reach it myself and I don't really want Ayda to do it. I did the crack (wax) thing and I did not like that. It was horrendous.''

Despite his reluctance to impose the grim grooming regime on his wife, Robbie and Ayda - who have been married since 2010 - have a very honest and open relationship and are the same with their two children, daughter Teddy, four, and two-year-old Charlton, together.

The 42-year-old pop star is enjoying every aspect of fatherhood but he is looking forward to when his kids get older and he can embarrass them.

Robbie - who appeared on the final of 'The X Factor Australia' at the weekend to sing with finalist Davey Woder - said: ''At some point I can put my foot down and go full embarrassment ... I probably will be like, 'OK, you think I'm embarrassing by just being me, check this s**t out.' I will get competitive with my embarrassment.''