More than 600,000 public sector jobs have been lost since the coalition came to power, with fresh cuts set to take the total to a million by the time of the next election, according to a new study.
The GMB union said its research showed the "devastating" impact of the coaliton Government's austerity measures.
As well as the job losses, the pay of public sector workers had been held down in the past few years, forcing them to accept a wage cut, said the union.
The study showed that 631,000 public sector jobs had been cut across the UK since the last election, with up to 400,000 expected to be axed in the next two years.
The biggest percentage cut has been in the South West (13.9%), followed by the North East (13.8%), West Midlands (11.5%) and North West (11.4%), said the GMB.
National officer Brian Strutton said: "These new statistics show the devastating effect of this Government's austerity cuts on total public sector employment.
"In particular, some parts of the country that are most dependent on the public sector to support their local economies have been hardest hit.
"The tragedy is that the worse is yet to come. The Office for Budget Responsibility's forecast for net total public sector job losses during the lifetime of this Parliament means that the prospect for the next two years could be up to a further 400,000 job losses.
"The evidence on the ground supports this, with our feedback from the current round of council budget reviews for next year suggesting accelerating cutbacks. A s a result, many communities in some of the most deprived regions will find their local economy in tatters.
"GMB representatives from around the country are reporting that public sector workers are fed up with being told they have to accept pay restraint and reductions to their terms and conditions to protect their jobs and their local services only to find that the jobs and services go anyway."
The union is holding a national meeting of senior stewards on Friday to discuss how to respond.