Taylor Nelson Sofres remained defiant in the face of a bid from WPP but gave an indication of the price the board would be prepared to consider as the battle for control of the marketing services group edged closer to a conclusion.

David Lowden, chief executive, said the current offer from Sir Martin Sorrell was at a multiple to earnings before interest, tax, depreciation and amortisation of about 11, whereas historically companies in the sector had sold for multiples of 14 or more.