
The business was previously handled by MWO, which held the account for five years and created the Britton ads. The tie-up gained notoriety last year when it emerged that the TV presenter had used a gastric band to lose weight.
It is understood that agencies were asked to come up with ideas that did not include the presenter during the pitch process. A spokesman for Ryvita said there were 'no plans for a change as yet' to Britton's ambassadorship.
Grey was appointed after a three-way pitch that also included BMB and VCCP, overseen by Jordans marketing director Carol Welch.
Welch took responsibility for the Ryvita brand following a restructure earlier this year by Associated British Foods, the parent company of both brands.
VCCP's tenure on the Jordans Cereals account is not affected by the appointment of Grey London.
Last month, Ryvita teamed up with IPC Media magazines to launch its Summer Fit Challenge campaign. The 14-day eating plan was intended to drive awareness of the range of nine Ryvita Crispbread variants and its Minis and Thins.