SIPTUm the countries largest trade union rejected a new public sector pay deal on Tuesday and warned the government that it would face a “major confrontation” if it went through with a threat to cut their pay unilaterally.

The government and the country’s main unions agreed in February to extend a three-year-old pay deal that has been credited with avoiding the kind of industrial unrest seen in other euro zone countries hit by debt woes.

But the deal had to be approved by hundreds of thousands of union members and after a number of smaller unions voted against the new proposals, it required the backing of SIPTU, whose members account for around 25 percent of all workers.

The union rejected the deal, which proposed pay reductions for higher earners, longer working hours and cuts in premium Sunday payments, by a margin of 54 percent to 46 percent.

“The result reflects the deep and well justified sense of grievance among working people throughout the country and public service workers in particular,” SIPTU president Jack O’Connor, who negotiated the agreement, said in a statement.

“We urge the government not to proceed with legislation to cut the pay of public service workers as it would inevitably precipitate a major confrontation.”

The update to the Croke Park agreement – named after the sports stadium in which the original deal was struck – aims to save 1 billion euros (849 million pounds) over three years, a key part of government efforts to reduce its budget deficit under the country’s 85-billion-euro EU-IMF bailout.

Prime Minister Enda Kenny told parliament after the vote that the government would reflect on the implications of the ballot results but reiterated that it would still need to find the 300 million euros worth of savings from the public sector pay bill identified for this year.

Public servants took wage cuts averaging 15 percent before signing up to the first Croke Park deal in March 2010, promising a leaner public service and industrial peace in return for no more pay cuts or compulsory redundancies.