Benefit chiefs rejected fresh claims a flagship welfare reform was "on the edge of disaster" after it was announced a full trial of the new Universal Credit will start at just one Jobcentre.
Ashton-under-Lyme will accept claims under the new combined benefit from April while Wigan, Warrington and Oldham will initially test only a "commitment" signed by claimants setting out what they will do to find work before dealing with claims from July.
Universal Credit is due to be rolled out nationally from October.
A DWP spokesman said the timetable was "entirely consistent" with a previous claim it would "go live" in all four areas from April.
Work and Pensions Secretary Iain Duncan Smith announced last year that the trial "is expected to see up to 1,500 new Universal Credit claimants coming on stream across four areas - Tameside, Oldham, Wigan and Warrington - each month".
His Labour shadow Liam Byrne said beginning a full trial in just one area was "yet another embarrassing setback for Universal Credit" and that the IT systems for the scheme "appear to be nowhere near ready".
"This scheme is now on the edge of disaster. Ministers must admit this project is in crisis and start to fix it now - before millions of families tax credits are put at risk," he said.
But the DWP insisted there was no delay.
"Our plan has always been to test Universal Credit in a safe and controlled way during Pathfinder to ensure we get it right for the start of the national rollout in October."