Business organisations have generally welcomed this week's partial climbdown by the Treasury on its plans to increase taxes for foreigners domiciled in the UK.
It followed confirmation by Chancellor Alistair Darling that so-called 'non-doms' will be only taxed on the earnings they bring in to the UK and not their worldwide tax affairs.
There had been heavy criticism of the plans and fears that a significantly harsher tax regime could spark an exodus of talented foreign workers.
But now a West Midlands expert has warned that the legislation was still likely to impact far more people than the super rich for which it is intended.
He warned it could render the West Midlands as an increasingly less competitive destination to set up business.
The new rules, to be introduced in April, aim to tax those who work in the UK but hold their assets and wealth in another country, often a tax haven.
They require these non domiciled residents that have lived in the UK for more than seven years to pay tax on their worldwide income and gains, or pay a £30,000 annual levy.
Joe Pilley, a director in Ernst & Young's human capital team, says that while the proposals will be effective in taxing the very wealthy non UK nationals working in the UK (non doms), the new rules are also likely to snare regular salaried employees seconded to work in the UK.
Mr Pilley continued: "If non doms choose to pay the £30,000 they will also be unable to claim their personal allowance of £5,000 of tax free income, resulting in an increased tax cost of around £32,000 per annum. These charges will not only apply to those non doms employed in the UK but also to their non working spouses as well as any children with significant assets."
Even those non doms that are here in the UK for short assignments, well below seven years, will have to pay extra tax as they will have to choose between on the one hand, paying tax on their overseas income and on the other hand, losing their tax free personal allowance.
Many businesses in the region with international operations use non domiciled workers seconded in from their overseas businesses, and it is common practice in these cases for the employer to pay the employees' PAYE on their behalf. As a result it is local employers who will be stung with the additional tax charges.