MPs are to investigate the decision by HM Revenue & Customs to pay an informant £100,000 for the bank account details of taxpayers with cash stowed in the tax haven Liechtenstein.

‘I am certain that at some point they will be required to come and explain what they are doing to Parliament. I would expect both the Treasury Committee and the Public Accounts Committee to look into this,’ Labour Treasury Committee member Jim Cousins said.

HMRC confirmed this week that it had paid a former employee of Liechtenstein bank LGT for the details of account holders. Acting chairman Dave Hartnett said the taxman expected to recoup £100m in tax with the information.

Politicians have been supportive of the decision to buy the information, which was also sold to German tax authorities who used it to launch tax investigations into 700 people, including former Deutsche Post chief executive Klaus Zumwinkel.

Liberal Democrat shadow chancellor Vince Cable said it was worth going through the ‘tricky business’ of paying informants to fight ‘large-scale tax avoidance and perhaps evasion by extremely rich people’.

Treasury select committee chairman John McFall told Accountancy Age this week: ‘This is one of the issues that may well come up [when we meet HMRC].’