The government has today unveiled what it said was an unprecedented package of measures to tackle tax avoidance, evasion, fraud and error.
The package would raise £9bn for the Treasury over the next five years, George Osborne said.
Measures include preventing employment intermediaries from disguising employment as self-employment to avoid tax, and introducing a new power requiring taxpayers using avoidance schemes that have already been defeated in the courts to pay the tax they are trying to avoid upfront.
Osborne was delivering his Autumn Statement in the House of Commons on Thursday.
BBC Business editor Robert Peston said: "The tax avoidance measures sound quite ambitious - and may well be causing jitters in the City."
Neal Todd, of international law firm Berwin Leighton Paisner, questioned the need for extra tax measures beyond the General Anti-Abuse Rule (GAAR), said: "Ensuring individuals and multi-national corporations pay the right amount of tax is a laudable objective but the latest announcements beg the question of why additional reform is needed.
"We already have the General Anti-Abuse Rule in place which was intended precisely to act as a catch-all framework to ensure the spirit as well as the letter of UK tax legislation is obeyed.
"Imposing the most wide-ranging anti-avoidance package in this Parliament on top of the GAAR and so soon after the GAAR was implemented will lead to unnecessary uncertainty about the interplay between various sets of anti-avoidance provisions. It can only further lengthen the UK tax code."
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