Gordon Brown delivered a stark warning to angry prison officers today that he will not back down over their delayed pay deal.
The Prime Minister said staggering of public sector rises was "essential" to keep inflation under control.
The Government would not do anything which put economic stability "at risk", he insisted.
Thousands of prison officers walked out yesterday morning in protest at the controversial decision to bring in their 2.5% award in two stages - which unions claim reduces its real value to 1.9%.
Union leaders will meet Justice Secretary Jack Straw tomorrow in an attempt to break the deadlocked row.
General secretary Brian Caton said today that all the striking prison officers returned to work last night after the union's executive decided to call off the action.
Prisoners in Leeds stood and applauded the staff, while in Chelmsford, Essex, inmates shook the hands of returning officers, said Mr Caton.
The Ministry of Justice said fresh talks had already been agreed before the strike took place but this was flatly denied today by Mr Caton.
He insisted that the industrial action forced the Government to agree to hold new negotiations over pay and deal with other complaints about the level of assaults against staff as well as cuts in prisons budgets.
But Mr Brown - who was responsible for the decision to stagger the pay deal as chancellor - signalled that he was not willing to back down on the crucial issue.
"We have succeeded in tackling inflation and having a stable economy because of discipline in pay over the last 10 years. That discipline will have to continue," he said on a visit to a health clinic in central London.
"Staging of pay awards is an essential part of the economy to ensure we have stability and so that can continue," he said.
"We will not do anything to put that at risk."
Mr Caton said two prison governors were attacked during the strike yesterday, which he regretted, but he pointed out that eight prison officers were now being assaulted every day, a huge increase on recent years.
He revealed that he will be pressing the Government to give prison officers the right to take industrial action which was taken away by the Conservatives in 1993.
"We want back our trade union rights and then we would be able to give notice of any industrial action," he said.
Mr Caton warned that unless there was an improvement in industrial relations and a breakthrough in the pay row, further strikes could be held.
The POA does not expect to face any further legal action following an injunction obtained by the Government yesterday in the High Court.
POA officials said the injunction was never served on the union and made it clear the only reason the strike was called off early was because of the promise of new talks.
"The strike was a reluctant success. It was entered into reluctantly but we have got we wanted out of it which is talks with Jack Straw and senior Prison Service officials," said Mr Caton.
He added that paying the 2.5% pay rise in full would be a "pittance".Reuse content