Gallant makes $79,000 a year on top of his $85,000 salary as a member of the legislature, while cabinet ministers make $52,614 in addition to what they earn as members.
The pay cuts will see Gallant's salary drop to $152,150 from $164,000 and cabinet ministers will have their earnings go to $132,253 from $137,614 as of April 1.
Gallant said the move is intended to show leadership at a time when the province braces for cost-cutting measures that could include concessions from government employees.
"There's no doubt that we're going to ask all New Brunswickers to take on some difficult decisions and that will include the civil service," he said Monday.
But Danny Legere, president of the New Brunswick wing of the Canadian Union of Public Employees, said his members aren't willing to consider wage rollbacks.
"Many of my members live paycheque to paycheque," said Legere, who represents 30,000 unionized government employees. "They will certainly get the strongest possible resistance if they try to roll back wages in the public sector."
The province has been in the red for the last six years and its deficit is forecast to be $377.2 million for the 2014-15 fiscal year. Its net debt is expected to top $12 billion in March.
The salaries of legislature members is due to be independently reviewed later this year, but Gallant said he will not support an increase in their pay.
"With the finances where they are right now ... it is not the time to have an increase in the salaries of MLAs and that's why I would not let it pass in the legislature," he said.
But Opposition Progressive Conservative Leader Bruce Fitch said the government shouldn't interfere in the outcome of the review.
"You should follow those guidelines because it is supposed to be an independent board made up without political interference," he said.
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