Justin Timberlake says his girlfriends never match up to his mother.

The 'Social Network' star - who is in a relationship with Jessica Biel and has previously dated Cameron Diaz and Britney Spears - is very close to his mother Lynn Harless, who is also his manager, and insists she is his "best friend".

He told the Daily Mail newspaper: "We're best friends - she's a very special woman.

"She's been so supportive. She's partly the reason why I have so much respect for Women. I'm never going to find someone as good as my mother, am I? Maybe that's why I have such problems with girls."

Justin credits his mother and father Randall Timberlake - who divorced in 1985 when he was just four years old - for keeping him grounded and unimpressed by fame, although he realises how lucky he is to be able to make a living from singing and acting.

He said: "My parents instilled In Me the mindset of always being humble. I'd like to think that all that teen idol stuff went in one ear and out the other with me.

"Now when I'm on the red carpet I'm just there to do a job ... but it is the coolest job in the world."