Foreign banks may face a "public perception that they have something to hide" if they do not co-operate with a new offensive to prise open secret offshore accounts of wealthy Britons, Revenue & Customs has warned.

Dave Hartnett, director-general, warned banks against taking a confron-tational approach to the Revenue, which has asked them to disclose whether they have access to information on offshore accounts. "The more confrontational it becomes, the more difficult it is for banks," he said in an interview with the Financial Times.