The acquisition by Sir Martin Sorrell's WPP of US advertising group Grey Global has been approved by the European commission.

The announcement clears the way for shareholders of Grey, the seventh largest advertising group in the world, to vote on the £800m cash and share acquisition.

The regulator said in the statement it found "there was no risk that the creation of the new entity would bring about a significant impediment to competition".

The EU unexpectedly asked for more information on the deal last November, concerned about the market power WPP would wield after combining its media buying companies, Mindshare and Mediaedge:cia, with Grey's MediaCom.

WPP's acquisition will see it responsible for the advertising of brands for arch rivals Unilever - whose brands include Dove and Persil - and Procter & Gamble, maker of Pantene and Clairol.

WPP expects to complete the acquisition of Grey by early March, which will rank it on a par with Omnicom, the world's largest advertising group.

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