The strength of the backlash against boardroom bonuses will be tested further next week when WPP asks investors to approve a scheme that could see its chief executive Sir Martin Sorrell earn as much as $95m (£60m).

Known as the Leadership Equity Acquisition Plan III (Leap), the scheme has been put in the spotlight after the Association of British Insurers last week gave members a so-called “red top” warning, encouraging them to look closely at the scheme before approving it.