Universal Credit is now live in seven areas across the UK and will be growing to ten by spring 2014. By the end of next year, the scheme will expand to cover more of the north west.
But the Government has admitted that about 700,000 claimants of a disability benefit will not be transferred to the new Universal Credit before 2017.
The Universal Credit reforms are intended to help people back into work but the Department for Work and Pensions said its priority throughout had been the "safe and smooth" delivery of the new policy.
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In his first outing since the referendum result, the lead Leave campaigner has outlined his vision for a post-Brexit Britain.