The company's future was thrown into doubt earlier this year after Cordiant announced it was to demerge, floating separately two of its advertising businesses - Bates Dorland and Saatchi & Saatchi - on the stock market. Morgan has approached several media groups.
Zenith is to be jointly owned by Bates and Saatchi, although a separate flotation has not been ruled out. The demerger plan has left all three companies vulnerable to takeover, and Zenith has been attempting to tie up a partnership with another agency - in part as a defensive move to deter predators.
A Morgan insider said that the plan to put together a deal was just a "bright idea", and that the investment house was not acting for Cordiant or Zenith. It is understood advertising agencies and media owners have been approached, but that no single party has entered serious discussions.
A source close to Cordiant admitted: "A number of people are scratching their heads deciding how to make a quick buck out of the parts of Cordiant."
But a spokesman for the holding company said selling Zenith was not on the agenda. He added: "Zenith is owned by Cordiant and it is not for sale. It is part of the architecture of demerger."
He said SBC Warburg was the company's investment bank of record.
No one at Zenith was available for comment last night.
Potential buyers for Zenith could include Martin Sorrell's WPP - which recently paid pounds 10.2m for a 14.4 per cent stake in another media buyer, CIA Group - Aegis, and CIA. Some City sources also suggested management might be interested in buying the outfit.
However, City analysts were unsure how much Zenith could fetch as much of its business is shared with Bates and Saatchi. The company's clients include Burger King and Mars.
Some observers said Zenith was also especially hard to value since several senior executives - in particular Christine Walker, Zenith's high-profile chief executive - had left the company in recent months. Cordiant is capitalised at almost pounds 600m.