Vodafone, the world's biggest mobile phone company, will have to bid for AT&T Wireless without Goldman Sachs, its most trusted adviser.

NTT DoCoMo, Japanese mobile phone provider, has retained Goldman to advise on the upcoming $30bn (€24bn) auction of AT&T Wireless. Goldman advised DoCoMo, which currently holds 17% of AT&T Wireless on its $18.4bn initial public offering in 1998.