An influential group of MPs said giving the taxman the power to recover money directly from personal bank accounts without some form of prior independent oversight would be "wholly unacceptable".
The Commons Treasury Committee also dismissed George Osborne's argument that the Department for Work and Pensions (DWP) already had similar powers to collect child maintenance.
The parallel is not exact: in those cases, DWP is acting as an intermediary between two individuals.
HMRC [HM Revenue and Customs] would be acting not as an intermediary between two individuals but rather in pursuit of its own objective of bringing in revenue for the Exchequer.
More top news
Police in Catalonia said the man killed was wearing what looked like an explosives belt.
As Big Ben falls silent for four years of renovation work, why not test your knowledge of the iconic London landmark?
Female football fans were asked to show their bras to stewards during security searches, a supporters' group has said.