The agency denied numerous reports that Simon Bolton, the JWT chief executive, is attempting to strip MacAuslan of his post.
It appears JWT's most senior management has acted to retain MacAuslan and is now seeking to find him a new role within the network.
MacAuslan has overall responsibility for JWT's Diageo business and the agency is now considering offering him an international role on that account on a consultancy basis. However, it is not clear whether this is a position that MacAuslan would wish to take up.
Diageo is known to have been displeased with the news and has been instrumental in the agency's attempt to find a new role for him. One source said that Diageo was "furious and upset at the news".
Another indicated surprise and questioned JWT's treatment of its long-serving deputy chairman.
Bolton said: "There is currently no change in Harry MacAuslan's status at the agency. He is not leaving."
MacAuslan, 47, joined the agency as a graduate trainee 24 years ago.
He worked across a number of accounts, including Barclays, British Bakeries, Nuclear Electric and ITV.
He was named a board director in 1989 and his famous gentlemanly manner helped him rise through the agency's ranks to become the head of account management in 1993. He was promoted to the position of deputy chairman in 1996.
MacAuslan said: "It's still business as usual. I will remain at JWT, but I may be doing something different."
The questions surrounding MacAuslan's position come during a period of change for JWT's senior management team. Earlier this month, the agency announced it was looking for a new managing director following Ros King's appointment to the role of global business director on Kraft Foods.
Miles Colebrook, the group president of JWT and a close colleague of MacAuslan, announced last autumn that he plans to retire by the end of 2004.