A Quebec union representing over 100,000 public workers in health care and social services has rejected a tentative deal with the provincial government.

The FSSS-CSN Wednesday refused to sign the agreement-in-principle offered by Quebec in December 2015 after months of contract negotiations.

The provincial government has already vowed not to budge on its current offer, stating it would not be fair to workers who accepted the current deal.

The majority of public sector unions representing teachers, healthcare professionals and civil servants struck a deal with the government after months of rotating walkouts.

Monday deadline

Treasury Board President Sam Hamad gave the CSN until Monday to get the FSSS on board with the government's offer. 

He did the same for Montreal's largest teachers' union, the FAE, which also voted down the agreement-in-principle.

"Improving the offers to the FAE and FSSS would break with the principles that guided the negotiations. The government has to act to preserve the quality of public services while respecting its financial framework," Hamad said in a news release.