A WPP firm is behind the BBC2 branding

WPP said like-for-like revenues in the July-to-September period grew by 5.7%, and added it was attracting new business "at an unprecedented level".

WPP won $1.5bn of new business in the first month of the fourth quarter from firms such as Nestle and Toys R Us.

But it said the "jury remains out on 2005" because of worries over the strength of the US economy.

"There are still concerns about the prospects for the United States economy after the presidential election, with its fiscal deficit, weak dollar and rising commodity prices, including oil," the company said.

"If industry growth rates this year are 3-4%, next year will probably be at 2-3%."