101 will develop a communications strategy and positioning for the brand in the UK.
It will create it a TV ad for the brand, which is expected to roll out later in the year.
The agency was appointed without a pitch.
101 opened its doors only 18 months ago and is headed up by the Fallon founding partners Laurence Green, Richard Flintham and former Cadbury marketing director Phil Rumbol.
At the end of last year it launched a series of press ads, created by Isobel, with the image of the ingredients created by a montage of hand prints. Isobel previously created a TV campaign for Kettle Foods.
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