MPs have waved through plans to raise the state pension age for women despite strong opposition, after the government offered to hold talks with critics about how the change would be introduced.

Despite anger about the move on all sides of the Commons, work and pensions secretary Iain Duncan Smith refused to delay the timetable for reform.

But he acknowledged the concerns of potential rebels and averted a backbench revolt when the Pensions Bill received its second reading last night.

Under the legislation, the retirement age for men and women is to be equalised at 65 in 2018, rising for both to 66 by 2020. It is currently 60 for women.

Ministers have been warned that it discriminates unfairly against women in their late 50s, who will now have to wait longer than they had expected to receive their pensions.

But Mr Duncan Smith insisted that it would affect only a “relatively small number of women” and that delay would cost the taxpayer £10bn.

He offered to hold “discussions” with MPs over the “transitional arrangements”, but maintained: “We stand by the need for men and women’s state pension ages to equalise in 2018.

“And both will rise together so the state pension age reaches 66 in 2020. This bill will go forward on that basis.

“If we delayed the move to 66 until 2022 it would cost the taxpayer £10bn - an unfair financial burden borne disproportionately by the next generation.”