The news comes as JWT parent WPP Group enters into exclusive talks to buy Cordiant Communications after French rival Publicis Groupe refused to enter into a bidding war.
B&Q put its account up for review at the end of May and was another serious blow to Cordiant, coming as it did on the heels of the loss of Woolworths, Royal Mail and Allied Domecq, which precipitated the whole set of crises at Cordiant.
The deal means that even if WPP wins or loses in its bid for B&Q, the account will likely end up somewhere within the advertising holding company.
If WPP's bid fails it is thought that the Bates team running the B&Q account will move to JWT, with the account marking the end of almost 20 years at Bates. Its TV advertising consistently tops Marketing's Adwatch chart.
Hiring the Bates UK team currently working on the B&Q account is understood to be a condition of the business moving, set by the retailer's marketing director David Roth.
However, if WPP's bid is successful the B&Q business will remain within Bates, which would then, as a WPP agency, have the support of the holding company's resources.
It is understood that as well as JWT, Roth has held talks with M&C Saatchi and Publicis-owned agencies Leo Burnett and Saatchi & Saatchi.
B&Q ranks at number 35 in the top 100 UK advertisers, according to Nielsen Media Research.
Roth's decision to open talks with other agencies was thought to be related purely to concerns over what would happen to the account should Cordiant collapse. He was said to be happy with Bates' performance on the creative account.
Roth, who was unavailable for comment, is understood to be less concerned about the tenure of B&Q's media buying account because it is currently held by ZenithOptimedia, in which Cordiant holds only a 25% stake.
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