George Osborne once praised Harriet Harman as making a "huge contribution to British" politics, but the chancellor's latest policy may indicate that his admiration does not stop there. The top Tory unveiled on 4 October that millions of grandparents across the UK will be given the opportunity to take time off to help care for their grandparents under an extension of flexible parental leave.

The move has been dubbed "granny and grandpa leave" and is designed to encourage more people to stay in the workforce for longer in a bid to boost the economy. "More than half of mothers rely on grandparents for childcare when they first return to work after having a baby," Osborne said, adding: "In many families, grandparents play a central role in caring for their grandchildren and helping to keep down the costs of childcare.

"Increasing numbers of grandparents, however, also want to remain in work themselves. Research shows‎ two million grandparents have either given up a job, reduced their hours or taken time off work to look after their grandchildren.

"Allowing them instead to share leave with their children will keep thousands more in the workplace, which is good for our economy. This is a modern Conservative policy that backs working families and gives them the freedom to choose what will work best for them.

"We will work with employers to make sure that we introduce this as simply as possible. It's an opportunity for employers who want to retain older members of their workforce, who might otherwise choose to leave the workforce permanently."

The policy is remarkably similar to a pre-general election proposal put forward by Harman in Labour's women's manifesto, which would have enabled grandparents to share 18 weeks of unpaid leave.

"Parents are increasingly relying on other family members to help them juggle work and childcare – particularly grandparents – with more than half of mothers relying on grandparents when they go back to work," the document stated. "So we'll do more to support families, consulting on allowing parents to transfer some of their unpaid leave to grandparents who want to help care for their grandchildren."

But under Osborne's proposal, parents can split up to 50 weeks of leave and a maximum of 37 weeks of parental leave pay with a grandparent. However, the draft legislation states that the relative has to be in employment.