Coldplay frontman Chris Martin has collaborated with Rihanna, Jay-Z and many others, but he draws the line at Justin Bieber. His refusal to team up with the young pop star has nothing to do with music, though.

"Justin Bieber is too handsome for us," Martin confessed during a recent interview. "If he wants to do a video with four people who look like his grandparents then we should be in it." The talented father of two is only 35 -- an age that not many consider to be ancient -- but when placed next to the bright-eyed 18-year-old, Martin feels much older. He doesn't believe that his looks hold a candle to Bieber's "amazing complexion."

Despite his inferiority complex (as far as looks go), Martin shows no signs of slowing down. In fact, he's currently on tour with his band to promote their chart-topping 2011 release of 'Mylo Xyloto' and will be hopping from one country to the next through the upcoming summer and fall.