TWO US senators who heavily criticised Ireland's corporate taxation regime say questions remain about whether enough is being done to tackle tax avoidance.
But the US politicians added that "important questions" still remained.
In a statement they outlined their concerns, including "whether the new rules will continue to allow Irish subsidiaries to dodge taxes by, for example, excluding substantial income from the 12pc Irish tax rate".
They also warned about companies "calculating taxable income in ways that produce a lower effective tax rate, or simply declaring tax residency in a tax haven with no corporate tax".
Earlier this year, a US senate committee on Apple's tax affairs drew negative attention to the company's activities in Ireland.
The senators published a highly critical 40-page report over the summer outlining what they claim is Apple's use of Ireland to avoid paying huge amounts of tax.
Mr Levin called Apple's tax strategy the "holy grail of tax avoidance" and sparked a dispute with Taoiseach Enda Kenny by referring to Ireland as a tax haven.
Mr Noonan's department released an international tax strategy mission statement alongside the Budget that contains measures to clamp down on agile tax planning moves such as the notorious 'Double Irish'.