Allen & Overy (A& O) has secured its biggest deal for Shell Chemicals since Shell’s review of its panel in November last year, acting on the $4.4bn (£2.4bn) sale of the energy giant’s plastics division Basell.

The deal, which A& O secured following a cl osed be auty parade in August 2004, saw the sale of Netherlands-based Basell to a consortium led by New York-based Access Industries and Chatterjee Group.