Fergie is planning to wear purple, red or black on her wedding day.

The 33-year-old ‘Big Girls Don’t Cry’ singer has revealed she won’t be in the traditional white when she marries ‘Transformers’ star Josh Duhamel in Los Angeles on Saturday (10.01.09).

She said: “Don’t expect me to be in white. Maybe I’ll be in black or red or purple.”

No matter what colour the dress is, friends say it will be “classic and simple” and probably designed by Calvin Klein, the singer’s favourite red carpet designer.

In preparation for the big day, the Black Eyed Peas singer – who has been dating Josh since 2004 – has embarked on a strict health regime to lose weight she put on to play a prostitute in the upcoming musical movie ‘Nine’.

A source said: “She’s working out hard. Every day she does cardio and free weights. She tries to keep moving as much as possible.”

The star has also banned sugar and carbs from her diet to make sure she looks perfect when she walks down the aisle.

Another source said: “She just wants the day to be magical, and have all of the people who have touched her life be a part of a day she’ll remember for the rest of hers.”

Rumoured guests include Justin Timberlake and his girlfriend Jessica Biel, Kate Hudson, Penelope Cruz, Daniel Day-Lewis, Shia LaBeouf and Megan Fox.