Hip-hop producer Pharrell Williams has hit back at his critics in the skateboarding world, accusing them of being ungrateful for the publicity he has given the extreme sport. Williams, who has produced hits for the likes of JAY-Z, Justin Timberlake and Gwen Stefani, regularly refers to himself as Skateboy P, and also has a skate-inspired fashion line called Ice Cream. He experienced a backlash from the sport's fanatics last year (05) when they printed T-shirts reading, 'Pharrell Can't Skate' - accusing the star of exploiting the industry to increase his street credibility. He tells the New York Post, "I was honoured. I never said I was going to skate. I can't see why anyone would ever be mad at me for helping to push the door open for everybody else. It really influenced a big part of my life, just like music did. "I learned jazz progressions in band, and I gave entirely back to that world. I go and speak in high school, colleges - Oxford once, Harvard twice. It's not a new thing for me to give back. I just give back in every way shape and form."