Welfare assessments for people with disabilities will be made later than originally planned, the government has announced.
About 3.2 million people receive Disability Living Allowance (DLA), a payment of between £20.55 and £131.50 a week to assist them in leading independent lives.
From 8 April, it will be replaced by Personal Independence Payments (PIPs).
Now the timetable of assessments for the new benefit has been extended.
Originally, the government said that claimants already receiving DLA would be contacted between October 2013 and March 2016 and invited to make a PIP claim.
They would need to go through an assessment to check what award they were entitled to.
Esther McVey, a work and pensions minister, told the Commons that the vast majority of these assessments would now be made no earlier than October 2015.
This would allow time for an independent review of the first phase of the switch to be carried out in 2014.
Assessments will be carried out in the shorter term for those claiming for the first time, or whose circumstances have changed in a way that might affect the amount they can claim.
Anne McGuire, the shadow work and pensions minister, said that the original timetable of assessments was "unrealistic" and there was some concern over the start date of June 2013 for new claimants' assessments.
The government hopes to save £2bn as a result of the switch from DLA to PIPs, but some of the original proposals were met with concern by groups representing people with disabilities.