GlaxoSmithKline (GSK) is facing fresh allegations of corruption, following reported incidents in China and Iraq. Polish authorities have launched a criminal investigation against the UK's biggest drugmaker for allegedly bribing doctors to promote its lung drug Seretide, also known as Advair, which has worldwide sales of around $8 billion a year.

The country's Central Anti-Corruption Bureau, or CBA, said 13 people had been charged in the case.

GSK said a single employee had been disciplined for "inappropriate communication" in contravention of company policy, following an internal probe, adding that it was co-operating with the Polish authorities. The company said the allegations related to the way a respiratory disease programme was conducted in the Lodz region.

The UK's national broadcasting company, BBC, reported that the Polish investigation included 11 doctors and a GSK regional manager, charged over alleged corruption between 2010 and 2012. It said one doctor who admitted guilt was fined and given a suspended sentence, after accepting £100 pounds for a lecture he never gave.