Aegis is to hold a shareholder meeting on November 22 to consider Vincent Bollore’s nominations to the Aegis board.
Bollore is Aegis’ biggest shareholder with a 29% stake and is also the chairman and main shareholder of French advertising group Havas.
If Bollore’s stake reaches the 30% threshold he will have to launch a full takeover bid under UK rules.
In a statement, Aegis said: “Any nominee put forward by Groupe Bollore has an overriding conflict of interest that makes them inappropriate to act as a director.
“The board is strongly opposed to adding directors who may favour one particular shareholder group over and above the interests of shareholders as a whole.”
Earlier in the week, Publicis announced that it is looking for acquisitions, with rumours circulating that Aegis could be targeted (see ITV Welcomes Ofcom’s Public Service Proposals).