Any move to introduce regional pay for public sector workers would be resisted, the Public and Commercial Services union says.
With MPs debating the issue today (10), the union says regional or local pay rates would simply drive down wages and further depress local economies that desperately need investment, not more cuts.
The union has described chancellor George Osborne's proposal as "economically incoherent" because it would undermine the government's stated aim of helping to drive growth and development in the regions.
Public sector pay has already been frozen for two years, and Mr Osborne announced in his autumn statement in November that it would be capped at 1% for at least two years beyond this.
In April, ministers intend to impose an increase in pensions contributions for public servants that will hit living standards even more.
PCS general secretary Mark Serwotka said: "Regional public sector pay is the exact opposite of what our local economies need.
"Instead of allowing pay to be driven down to the lowest level, ministers should be looking to increase pay and living standards of everyone, to put money in people's pockets to help our economy to grow."