SIPTU has given a guarded welcome to the outcome of the European Parliament vote on the controversial EU Services Directive.
The measure aims to open up the services market across the EU and remove the red tape that discourages service-providers in one country from setting up in another.
Trade unions had expressed huge concern that aspects of the new law would exacerbate the erosion of employment standards, with companies from low-cost EU states undercutting their rivals in wealthier countries.
However, MEPs yesterday voted in favour of a range of amendments designed to protect workers' pay and conditions.
SIPTU president Jack O'Connor said last night that the amended directive approved by the parliament appeared to be a major improvement on the original draft.
However, he said it was too early to give a definitive assessment and SIPTU would be withholding its support until it saw the full text of the new law.
Mr O'Connor also said that, despite yesterday's vote, the onus still rested with the Irish Government to ensure that the pay and conditions for Irish workers are protected.