Merger talks between US giants Akin Gump Strauss Hauer & Feld and Shaw Pittman were called off last week, bringing an end to one of the largest potential tie-ups in US legal history.

The firms began talks in August and the merger would have seen 945-lawyer Akin Gump link up with 350-lawyer Washington DC-based Shaw Pittman to create a practice with a turnover of $767m (£452m).