Timberlake Accused of Cheating.

Justin Timberlake has been accused of cheating on Cameron Diaz, according to America's New York Post newspaper.

Sources allege the pop heartthrob is romancing a 26-year-old brunette beauty, known only as Monica, behind his stunning girlfriend's back.

A friend claimed to the newspaper: "Monica is telling everyone they are secretly dating. Cameron has no idea. They met because he has been hanging out with this crew from UCLA (University Of California Los Angeles ) that she is friends with."

However, Justin's spokesman denied the rumours, saying: "I don't think this is true."

It was recently claimed Justin and Cameron were having a trial separation because their 18-month relationship was on the rocks.But the couple then appeared as smitten as ever when they were spotted canoodling on a romantic Caribbean holiday.

Meanwhile, Cameron broke down in tears on Oprah Winfrey's TV show - over politics. The 'Charlie's Angels' beauty, 32, cried while urging women to vote in the upcoming US presidential elections.

She said: "Apathy did not create this country but it's going to destroy it."I'm really scared. We're really alone, where we used to be the strongest in the world, we're alone."

Cameron's emotional plea came after statistics revealed 22million US women did not vote in the 2003 elections, which put George W Bush into power.