The approach values Press Index at €11.2m (£9.1m). The firm allows communications and marketing professionals to access information about their company’s media exposure.

Should the initial WPP transaction be completed, the marketing services giant would then initiate an all-cash simplified tender offer to acquire the remaining outstanding shares in Press Index.

WPP will use a squeeze-out procedure if necessary and is offering a price per share of €6.81 (£5.54 ) in cash.

Earlier this week WPP became the latest major company to suffer a pay revolt as 60% of shareholders voted against chief executive Sir Martin Sorrell’s (pictured) controversial £13m pay deal.