Cameron Diaz and Justin Timberlake are expecting a baby together, the Daily Star claims today.

Timberlake's mother, Lynne Harless, apparently revealed the couple's happy news to her neighbours in Memphis, Tennessee.

"Lynne told us about a neighbour who had gone all out for Christmas because she'd had her first grandchild over - and she couldn't help grinning," one friend told the newspaper.

"She was asked if she was keeping a secret and burst out that it was going to be 'a very exciting year for Justin and Cameron' and that she hoped to have a baby over next December 25 - then added, 'I'm knitting booties.'

"She's been planning a huge birthday party for Justin's 25th at the end of the month and seemed to be hinting there could be an announcement then. It seemed pretty obvious that Cameron's pregnant."