Brand owner Kraft Foods said
10-year partnership had been a "difficult decision" and it was grateful to French for the "major impact" she has had on its advertising.
"After such a long partnership we feel that the campaign has run its course and we are in the process of developing different work," added marketing manager Stephanie Lea.
A new TV ad will
air this month showing an office work er break open a Terry's Chocolate Orange
only to have her colleagues steal it segment by segment when her back is turned as the famous Countdown timer ticks in the background.
It will run with the strapline Round, But Not Round For Long, and is part of a £2.3 million marketing
spend on the brand.