GfK, the market research group vying with WPP for control of Taylor Nelson Sofres, refused to confirm last night that its original financial backer for a bid was still in place.

This came after Sir Martin Sorrell, chief executive of WPP, said he wanted the Takeover Panel to force GfK to make clear whether its original financial backing was still viable.

A GfK spokesman said: “GfK was all set for a nil-premium merger with TNS until Sorrell barged in and changed everything. GfK needs time to realign its troops. This takes time and we are not in the easiest climate at the moment.

“We are in talks with serious and important investors and these talks are progressing very well. We will make an announcement at the right time.”

WPP, the second-biggest advertising group, split up an agreed all-share merger between GfK and TNS last month with a higher hostile bid made up of cash and shares. The Times revealed at the time that GfK was considering tabling a cash bid for TNS, a move that the German company confirmed.

“GfK's original statement regarding the financing of a bid for TNS should have been modified to clarify its situation,” a WPP spokesman said.

There are concerns that GfK is trying to raise new finance to replace its original backer, which has not been named, or to supplement its contribution. GfK is understood to have had the backing of the Herz family, of Germany. However, it has since been talking to a number of private equity groups, suggesting that the Herz family will provide little or no funding.

GfK's original statement on July 9 said: “GfK is actively pursuing a proposal which would involve an alternative all-cash offer being made for TNS with the involvement of an identified potential source of equity and equity-related financing.”

The comments from Sir Martin came as WPP issued results for the six months to June 30. Sir Martin

forecast that global financial markets would begin a path to recovery in mid-2009, although Britain would continue to be the advertising group's slowest growth market.

The group reported better than expected like-for-like sales growth of 4.3percent for the first half and raised its interim dividend by 20percent. First-half sales were £3.4 billion, beating analysts' average predictions of £3.2 billion. Pre-tax profit for the six months rose by 15.1 per cent, from £294.1 million to £338.5 million.

However, sales fell slightly in July, according to Sir Martin. “There was a slight slowdown in May and June. Since then it has been pretty much the same pattern. July followed a pretty similar pattern to the second quarter,” he said.

He added that, although the global economy could show signs of recovery in the middle of next year, the effects would not be seen until early 2010.

The company did not lower its forecast of 16 per cent profit growth for 2009, but said that prospects for next year were “less certain” because of the slowdown in Europe and America, while a spurt in business from China would drop off after the Olympics.

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