Singer Robin Thicke has joked about the days he used to sport a "Jesus perm".

The 36-year-old star's catchy hit 'Blurred Lines' featuring Pharrell Williams and T.I. has become an international sensation.

Thicke had success on a smaller scale before the No. 1 tune, and insists his look suffered as a consequence.

Laughing in an interview with Australian radio hosts Kyle and Jackie O he explained: "I had the long hair! Well, the funny thing was, I had always written and produced for others but I didn't devote time to my own music and I told myself I wouldn't cut my hair until I hear my own song on the radio.

He added: "That took about two years, so I ended up with this Jesus perm! There was no style, just a big, flowing head of hair."

Thicke has two versions of the accompanying promo to 'Blurred Lines' - a normal and a more risque edit, which features the models in his videos topless.

Thicke quipped: "Honestly, it was all the director's idea! I told her I just wanted to make a funny or silly video and she said, 'Well, what if the girls take their clothes off?'

He continued: "They were well paid! That's why the rest of us are just standing in front of a white wall; because all the money went to the girls' boobs! There's Treats! Magazine, it's a fashion magazine, but it's predominantly nude and Emily [Ratajkowski, girl from the video] was on the cover and star of the magazine and I gave it to the director as an idea, but she just got the girl!"