Vincent Bolloré's Havas has responded to a series of public attacks by Sir Terence Conran over international expansion plans for its Conran Design Group subsidiary with a letter maintaining it has a "legal and moral" entitlement to exploit the brand.

The letter, written in response to a letter faxed by Conran to Bolloré, the Havas chairman, on April 4 outlining his grievances at the proposals, agreed to a meeting to iron out differences.

Havas-owned ad agency Euro RSCG acquired the Conran Design Group in 1990, including the rights to use the brand internationally.

The 76-year-old designer, who left the company to form Conran Group Holdings, has hit out at Havas's plans to expand the business internationally.

"The press has quoted you as expressing surprise at our plans and suggesting that we should use a brand of or own," said Chris Pinnington, the global chief operating officer at Euro RSCG, responding on behalf of Bolloré.

"But Conran Design Group is our own brand, one that we paid a substantial amount of money to acquire and one that we have a legal and moral entitlement to continue to use and develop."

Pinnington added that it was a "basic reality of business" that "if you build a business using the name of the founder and sell it with rights to continue to use the name, you can't subsequently argue that it is wrong for the purchaser to expand that business using the name".

Havas has made the letter public after the Conran Group Holdings chief executive, Roger Mavity, was today quoted in the Daily Telegraph threatening to invoke a right the company still has to make spot quality checks and to veto any work under the CDG name.

Mavity, who sent a letter to Pinnington outlining the strategy, said that the company would visit any new CDG office and monitor output.

"I must say that we do not find the way your company has been approaching this matter in the press constructive," said Pinnington in today's letter to Conran.

"We regard it as essential that the Conran Design Group companies worldwide produce work of the highest quality.

"But I must make it clear that Mr Mavity's latest statements in the Daily Telegraph to the effect that you can act as 'editors' of our work simply do not reflect the agreement which you signed in 1990."

Pinnington added that Bolloré and the Havas management team had "no wish to go into battle" with Conran unnecessarily.

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