The Interim-Public Service Association in Tonga has rejected a government proposal to bring in independent auditors in a bid to end a wage dispute.
Thousands of public servants have been on strike for nearly three weeks.
The government's offer of an audit came in response to a petition and follows unprecedented marches to press for massive pay increases.
The Interim-PSA chairman, Finau Tutone, says the suggestion is unacceptable.
"The auditors will come. They are dealing with the numbers and so forth but there is a mixture of social and political things inside, so in that case, I think an auditor cannot deal directly with our need."
Mr Tutone says the workers are sticking to their demands of increases of up to 80 percent and they also want to be reassured that they will not get punished for striking.