The company took the decision to consolidate its advertising roster across the continent last year. Yakult has not replaced Wieden & Kennedy yet, but is expected to make an announcement before the relationship ends in April.
Yakult's decision to severe ties with the agency marks a U-turn on a previous statement made by the company.
In September, the company said the UK market would be unaffected by the consolidation, because it was attempting to increase its share of the probiotics market outside of the UK in the face of stiff competition from Danone's Actimel.
At the time, a spokesman for Yakult said: "Yakult has spoken to a number of pan-European agencies about the new territories we are moving into. This doesn't affect the UK business."
Wieden & Kennedy began working on the £5m Yakult business in June 2005 and devised a campaign to relaunch the brand, with a series of print and TV ads extolling the health benefits of the drink.
It is believed the company will now focus on creating a small roster of pan-European agencies, delivering an overarching European creative strategy.
At the time of writing, no one at Yakult and Wieden & Kennedy was available for comment.
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