An international group of senior politicians have written to the chairman of HSBC, Mark Tucker, urging him unfreeze bank accounts linked to a high-profile pro-democracy activist from Hong Kong. More than 50 members of the Inter-Parliamentary Alliance on China – including representatives from the UK, Canada, Australia, France, Germany and Switzerland – are calling for the immediate release of funds belonging to Ted Hui and his family, and a formal explanation of HSBC’s decision to freeze their accounts. The letter, which was first reported in the Times on Monday and is signed by politicians from 16 countries, including the former Tory leader Iain Duncan Smith, asks HSBC to publicly commit to protecting the accounts of customers who are facing “politically motivated charges issued by the Chinese and Hong Kong authorities”. It heaps pressure on HSBC, which has come under fire for backing China’s controversial security law in Hong Kong, and subsequently freezing the accounts of pro-democracy protesters such as Hui who critics say are the real target of China’s crackdown. Hui – a veteran activist and former member of the Hong Kong legislative council – fled to Britain late last year. HSBC froze his accounts in early December, shortly after Hong Kong police accused him of misappropriating funds and money laundering. Despite a brief reversal, HSBC accounts held by Hui and his family are still frozen. The letter said the freezing of the accounts was “detrimental not only to Hui and his family’s wellbeing but also gravely tarnish HSBC’s reputation as a socially responsible enterprise operating under the rule of law. These actions undermine the open societies and free economies that underpin HSBC’s success.” HSBC refused to comment on Hui’s case, but emphasised that it was not in a position to question requests from local police. “Like every bank, we have to operate within the law and legal frameworks of all the countries in which we operate,” it said. “When we get a specific legal instruction by police authorities in Hong Kong, or anywhere else, to freeze the accounts of somebody under formal investigation, we have no choice but to comply. Disobeying such an order would be a criminal offence.”