The car giant is leaving its £43m Peugeot business with Euro RSCG, however.
The win is a lifeline for Partners BDDH, which lost its £8m Mercedes account at the end of last year.
It is understood that the shift will result in redundancies at Euro RSCG, creative director Joakim Jonason among them.
The agency is also expected to close its second building, which was set up to keep the management of the Citroen account separate to that of Peugeot.
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