Britain has called on China to accelerate plans to share information in criminal investigations in a sign of a growing drive for co-operation between China and the west in global probes.

The move comes as GlaxoSmithKline’s chief executive, Sir Andrew Witty, confirmed it has been in contact with prosecutors on both sides of the Atlantic as well as the British government in the wake of the Chinese corruption probe engulfing the company.

A legal assistance treaty, which facilitates requests between countries for evidence, documents or individuals, has been agreed between China and the UK but not yet signed, according to people familiar with the situation. British officials have recently travelled to China to urge swift ratification, the people said.