Prime Minister David Cameron has lent his support to GlaxoSmithKline and its activities in China on a high-profile trip where he is being accompanied by the drug major's chief executive Sir Andrew Witty.

GSK has been accused of bribery in China and the firm's reputation has taken a battering there but Mr Cameron is in its corner. He is believed to have discussed the matter with China's top leadership and has also spoken to reporters in Shanghai to defend the company.

He was quoted by Reuters as saying that "from all my dealings with GSK, I know that they are a very important, very decent and strong British business that is a long-term investor in China". He added that "I think it is right to raise a case like that. Britain has a record of properly standing up for British businesses and British individuals, raising individual cases in the right way and…having a proper dialogue with the Chinese authorities about the issues".

Some people accused of being involved in the GSK scandal in China are still being detained by the authorities. Sir Andrew has yet to make any public announcement while on the trade trip but observers are expecting a comment soon.

At the end of the year, Sir Andrew will step down from his role as an adviser to the government at the Department for Business, Innovation and Skills at the end of December. He has completed his three-year term and in the summer GSK stressed his leaving is not related in any way to the China issues.