More than 4,000 frontline workers attended a rally in Tallaght to protest at Government plans to cut an extra €1bn from the State payroll bill over the next three years.
Government negotiators at the talks to extend the Croke Park deal have rejected claims by the 24-7 Frontline Alliance that they have targeted frontline workers disproportionately for cuts in earnings.
The alliance represents 70,000 nurses, prison officers and gardai,
Seamus Murphy of the Psychiatric Nurses' Association received a standing ovation, saying "no deal is better than a bad deal".
He also responded to the possibility of the Government introducing legislation to cut pay by saying: "They need to be careful. Do you remember what happened to the last crowd that cut our pay?"
He told the crowds that "in 1913 we had a lockout, in 2013 we have a sellout".
Garda Representative Association General Secretary PJ Stone warned the Enda Kenny that workers will not continue to deliver public services for the "miserable measly wage you think you can negotiate in the Croke Park talks".
Mr Stone accused Mr Kenny of threatening public frontline workers. He said they had never flinched from doing their duty.
He warned that the campaign would be resolute and determined.
He said this was the start of a campaign which would only end when the Taoiseach understood that they were not giving any more paycuts.
He said they could not be afraid of the consequence of actions when the cause was just and fair.
He received a standing ovation as the crowd chanted "no more cuts".
John Clinton of the Prison Officers Association warned against punishing those who had already made a massive contribution.
"They'll be trouble ahead, trouble that can be avoided if a just and equitable solution can be found which will not further punish those who have already made a massive contribution," he said.