The ACCA cited as an example, the changes to the taxation of partnerships, where the Government has implemented changes while the OTS is in the process of reviewing partnerships more generally, which it says ‘seems completely at odds with the reason for establishing [the OTS] in the first place’.

It said the withdrawal of personal allowance for those on incomes of over £100,000 has resulted in a marginal rate of 60 per cent on income between £100,000 and £120,000, when the rate drops back to 40 per cent before going back up to 45 per cent at £150,000. In addition, the implementation and interaction of individual elements in the taxation of contractors and the employment industry supply chain, such as the onshore intermediaries rules, have imposed additional burdens and complication.

Other examples cited include consistent rate changes to Annual Investment Allowances which counteract the benefit; transferable allowance for married partners which has resulted in potentially infinite marginal tax rates; and the UK’s unique fiscal year where the tax year is run six days in to a month instead of using the calendar year or at least aligning to the end of a month.

ACCA said the government has not given the OTS enough support or the time to do its work since its founding.

Jason Piper, ACCA technical manager, tax and business law said: ‘This is just a snap shot of continuing problems with the UK tax system, that the coalition could have made better, and indeed some areas where they have made them worse.

'The Queen’s speech gave a few indications about the government’s intentions for the coming year. Pensions in particular holds the promise of simplification, with the abolition of punitive tax charges on pensioners, but yet again the devil will be in the detail.

'With less than a year to go until the next election the government is limited to the time they have to make things easier but they can give the OTS more support in the time that remains in this parliament and set a precedent for future governments.’