The Garda Representative Association says the force will not be able to cope if its strength is reduced to 13,000 members.
At its annual conference, which opened in Westport this evening, the association also called for new legislation to be brought in to protect gardaí in the course of their duties.
Members will also debate a number of key issues including pay, the Garda Reserve and the Garda Ombudsman Commission.
General Secretary PJ Stone said the plan to reduce the force 'does not serve any purpose' and said gardaí 'are looked upon as a last bastion by vulnerable citizens'.
Gardaí in Donegal want court-imposed fines to be linked to a person's personal tax record and the collection of such fines be administered by the Revenue Commissioners.
Gardaí in Kerry want six more days annual leave in lieu of the pay cuts and no more high-speed pursuits until the regulations are changed, while gardaí in Dublin want continued investment in appropriate specialist forensic training.