A former HSBC employee who leaked documents alleging the bank helped wealthy customers dodge tax said Wednesday he had tried to alert British authorities about evasion in 2008.
The leaks about the Swiss arm of Britain's largest bank have caused shockwaves across the world and sparked a political furore in London.
In an interview with broadcaster Sky News, IT worker turned whistleblower Herve Falciani said that he had alerted British authorities in 2008 but had seen no result.
"I sent a mail, a very naive email in 2008, to England, to the department dedicated to tax evasion. Afterwards I even called them," Falciani said.
His comments may add to a political row in Britain, where MPs have accused the tax authority of not doing enough with the leaked information, which was shared with them in 2010 after Falciani gave it to French authorities.
The head of HM Revenue & Customs Lin Homer was shouted down by lawmakers in parliament as she tried to defend the agency's record on Wednesday.
Prime Minister David Cameron has been pressured by the opposition Labour Party to explain why he appointed the former head of HSBC Stephen Green as trade minister.
On Wednesday, a report in newspaper the Guardian said that seven donors to Cameron's Conservative party were among the HSBC account holders.
British tax officials say they have recovered $135 million ($206 million, 182 million euros) due to information gleaned from the files since 2010, but there has only been one prosecution.
The scandal broke after the content of the files was made public this week by the International Consortium of Investigative Journalists and media organisations around the world.
Falciani added that the information so far made public was a tiny fraction of what was available in the files.
Source: AFP