Only the broad goals of any deal have so far been released, which include the ‘regularisation’ or disclosure of currently untaxed assets held by UK citizens in Switzerland.
How far back this would stretch is currently unclear. The LDF covers the past 10 years, while other recent so-called tax amnesties have been set at 20 years.
A withholding tax is also to be introduced. The rate at which it will be set forms part of the negotiations, which began earlier this year.
It was announced last October that an agreement between the UK and the historically secretive financial centre was to be reached, when the Swiss revealed their Federal Councillor Hans-Rudolf Merz had been in discussions with UK chancellor George Osborne.
The pair signed a joint declaration signaling their intent to increase tax information sharing cooperation and improve market access for Swiss financial firms in the UK.
However, the possible terms of the deal are a source of concern to some, including Liechtenstein financial institutions which have benefitted from growing assets under management as UK tax evaders have moved funds to the country in order to disclose them without fear of prosecution or heavy penalties under the LDF.
Some tax experts have cautioned that if a deal similar to the LDF were to be struck, its terms would need to be carefully considered.
There has been speculation that anyone coming forward to Swiss authorities to declare unpaid taxes under any deal may be able to do so anonymously.
But tax investigators argue such anonymity would undermine the purpose of an amnesty, leaving tax evaders with the option to only partially disclose untaxed assets – those held in Switzerland – while keeping others stashed in other parts of the world hidden.
Andrew Watt, managing director, tax disputes and investigations, for accountants and business consultants Alvarez & Marsal Taxand, said: “I do not believe HMRC could countenance an arrangement under which UK tax evaders could settle unpaid liabilities while at the same time retaining their anonymity.”