Will.i.am is to feature on Cheryl Cole's second solo album 'Messy Little Raindrops'.
The pair - who appeared on four tracks on the British star's debut record '3 Words' - are said to have secretly laid down a number of tunes while the 27-year-old beauty was in Los Angeles earlier this month.
An insider revealed: "Will can't contain his excitement over the new stuff. He reckons the tracks will be even more successful than her first batch of solo tunes. He had a long recording session with Cheryl in Los Angeles last week and was gushing about it to a pal."
The Black Eyed Peas hitmaker - who is also working on recording his second solo album - also found time to appear with the 'Fight For This Love' singer to help film part of her TV talent search series 'The X Factor' in England, despite his "crazy schedule".
The source added to the Daily Star newspaper: "Will was so excited about joining her for the 'Judges' Houses' stage of the competition he changed the airline he was travelling on so he could get to the UK a couple of hours sooner.
"Will's a very busy man and he thrives on it. But he always manages to find space in his crazy schedule when it comes to Cheryl. They're great friends and he relishes making music with her."
'Messy Little Raindrops' is thought to be scheduled for release before the end of the year.