German market research company GfK has scrapped its merger plans and has made a renewed offer for Taylor Nelson Sofres in response to a rival bid.
WPP made a hostile bid for the market research company earlier today, offering 260.6p per share for TNS.
The bid came after a deadline set by the London Stock Exchange to 'put up or shut up' expired.
GfK had previously offered to merge with TNS but called off the deal after the hostile bid.
TNS rejected the offer and GfK has now ditched its attempt to merge with the company in favour of an all-cash offer, financed by an unnamed source.
"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 company said.
Donald Brydon, chairman of TNS, said: "The board has unanimously rejected the offer which substantially undervalues TNS. Shareholders should take no action and should not complete any form of acceptance in connection with WPP's offer."
This morning, chief executive of WPP Sir Martin Sorrell said: "We believe that the offer for TNS generates value for WPP share owners and offers TNS share owners both cash certainty and equity upside.
"The offer from WPP is a superior alternative to what is, in effect, a 'nil-premium' reverse takeover of TNS by GfK and a 'merger of unequals'. We remain willing, at the shortest of notice, to meet with the board of TNS."
TNS has moved to "adjourn indefinitely" its general meeting, scheduled for July 18th, to give GfK time to make another offer.