George Osborne targets £20bn of extra Whitehall cuts by 2020 in spending review

George Osborne will unveil how the government plans to slash another £20bn ($31bn) in cuts as part of his spending review in late 2015, the chancellor revealed today (21 July).

The top Tory, just weeks after his post-election budget, said he will outline on 25 November the extra savings needed to eliminate the UK's deficit by the end of the parliament in 2019/20.

"This spending review is the next step in our plan to eliminate the deficit, run a surplus and ensure Britain lives within its means," Osborne said.

"We'll invest in our priorities like the NHS and national security. Elsewhere in government, departments will have to find significant savings through efficiencies and by devolving power, so people have a greater say over the issues that affect them and their communities. We'll deliver more with less."

The chief secretary to the Treasury, Greg Hands, will now write to the government's ministries and ask the departments to draw up cost-cutting plans.

The Treasury said Hands' letters will ask departments to model two scenarios of 25% and 40% of savings within their resource budgets by 2019-20 in real terms.

"In making these savings, the spending review will also reaffirm the government's commitment to invest in the NHS and our national security, while protecting spending on schools and honouring our commitment to the poorest people in the world," the Treasury said.

"In order to protect these areas of spend, we will need to make large savings in other areas. The government is clear - it can achieve this while maintaining the public services people rely on, because it's been done it before."

The announcement comes after Osborne outlined £12bn worth of welfare cuts, including a reduction in child tax credits, as part of his controversial emergency budget.

But divides have opened within the Labour Party after acting leader, Harriet Harman, ordered the red MPs to abstain from voting on the Conservative's social security measures.

However, 48 Labour MPs defied the party's whips last night and voted for an opposition amendment tabled by Bishop Auckland MP Helen Goodman.

The Tories, as expected, were victories as 308 MPs voted in favour of the draft legislation and 124 against.

Iain Duncan Smith, the work and pensions secretary, said: "Nearly 50 Labour MPs have defied their leadership and opposed our welfare reforms which will move our country from a low wage, high tax and high welfare economy to a higher wage, lower tax and lower welfare society.

"It's clear that Labour are still the same old anti-worker party – just offering more welfare, more borrowing and more taxes."