GlaxoSmithKline's solid set of figures for the second quarter has been overshadowed by its woes in China and chief executive Sir Andrew Witty kept his cards close to his chest when discussing the problems.

Speaking about claims of bribery in China on a conference call, Sir Andrew said "I am personally very disappointed", adding that "they are shameful allegations". He went on to say that "I remain strongly of the view that the 99.9% of individuals in this organisation are absolutely operating in the appropriate way".

He noted that the investigation "appears to be focused on a number of senior managers, potentially defrauding GSK and doing something inappropriate and illegal". However, Sir Andrew went on to say that the probe is still at the early stages and that he could not provide any further details.

The CEO did say that management at GSK's headquarters in London knew nothing about the bribery allegations until they were made public by the Chinese authorities earlier this month. He added that he was "absolutely willing and ready" to go to China, but said he was happy with the way other senior management were handling the situation.

Sir Andrew ended the conference call by stressing GSK's commitment to "rooting out corruption".