In an email sent to colleagues, Sir Nick said that suggestions a colleague was trying to undermine his position as the number two executive at the company, after chief executive Bill Ford Jr, were "scurrilous".
Yesterday, Ford overturned a decision made by Sir Nick to consolidate all of its advertising and marketing into WPP Group following an internal inquiry. Ford spokesman Jim Bright said: "The incident is now behind us. Case closed."
The inquiry found that the decision Sir Nick took breached Ford's purchasing policies. If the directive had gone ahead, WPP would have faced no competition for new Ford advertising and marketing.
As it is, Ford is already WPP's biggest client and accounts for 7% of its revenues. Even before the directive was issued, or before it was discussed between Sir Nick and WPP in November, WPP was beating off rivals to win more Ford business.
In July, WPP extended its grip on Ford's global advertising business when it won the $50m (拢31.2m) US account for Land Rover. However, suggesting there is still a degree of openness in Ford's advertising allocation, earlier this year Aston Martin, the Ford-owned luxury British car marque, appointed German advertising agency Wensauer & Partner to handle its worldwide creative account. It is not a WPP agency.
Sir Nick sent the email in response to widespread speculation that there was a rift between himself and Ford executive vice-president David Thursfield, who is the head of international operations and global purchasing.
The source of the speculation is that Thursfield, another British executive, is seen as a potential successor of Sir Nick, who turns 60 later this year.
"I have worked closely with David for many years and I have complete trust in both his integrity and his loyalty. I know he would never even contemplate doing anything that might compromise the company. Should you ever hear a rumour that David and I are in competition, I ask that you intervene -- quickly and directly -- and stamp the rumour out," Scheele said in the email.
The decision to abandon the Sir Nick's "WPP directive" is seen as weakening his position and possibly tying WPP's fortune's at Ford to his.
"Marketing will continue to look at the idea. There is a group of marketing senior executives and people in finance who are having another look at it, to see if it is a wise decision from a cost standpoint," Bright said.
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