Representatives from JCDecaux could not comment further on Mulcock’s future whereabouts, saying only that he had resigned for personal reasons.
Mulcock has spent less than a year with the outdoor advertisers, having joined in late 2007.
Before joining JCDecaux, he was managing director for Dow Jones Greater China, where he was made redundant during part of the reshuffle which followed the restructuring of the enterprise media group in 2007.