Wychavon complained to the Audit Commission that the adverts run this July breached rules specifying council adverts must be informative not persuasive.
Radio and local newspaper adverts encouraged the public to 'leave the ridings to Yorkshire', a reference to a plan to create three unitaries, or ridings, in the county area. The county wants to see a unitary Herefordshire in combination with a two-tier Worcestershire.
Wychavon said the advertisements were suspended after talks with county auditor Price Waterhouse but the county said the ads had run their course.
Wychavon chief executive Tony du Sautoy said the district did not intend to take legal action.