Image caption Admiralty Arch is one of the many government buildings sold off in recent years

An efficiency drive across government to improve procurement and reduce property costs helped save £3.3bn last year, ministers have said.

The sale of surplus property and renegotiation of leases on government buildings helped generate £973m.

Better purchasing of goods saved £1.2bn while lower rates of fraud and error in welfare programmes saved £805m.

Ministers said they were on track to cut government costs by about £30bn over the five years to 2020.

The National Audit Office has said in the past that good progress is being made in saving money in individual areas.

But the public spending watchdog has said a far more "all-embracing" approach to efficiency is needed, rethinking the core functions of government.

The latest estimated savings figures, released on Friday, which relate to 2015-16, are not official but are based on departmental reports and other supporting evidence.

'Significant steps'

The savings drive has been underpinned by a shrinkage in the size of the government's property estate, with outdated buildings sold off and smaller departments sharing premises with larger ones.

The 2012 sale of the famous Admiralty Arch building in central London, which is being turned into a hotel, yielded capital receipts of £66m this year.

"We have made significant steps forward in tackling fraud, selling off redundant government property such as the former Civil Service College in Sunningdale and making better use of modern digital technology to drive savings," said Cabinet Office Minister Ben Gummer.

Mr Gummer acknowledged that meeting larger, long-term efficiency targets would depend on the "total transformation" of how government worked - requiring more public services to be delivered digitally.

Tackling waste and fraud in the payment of benefits, tax credits and government grants has been a priority, as has the quicker recovery of debts.

Figures released in December showed the amount of benefits not paid to those entitled to them owing to fraud and error rose had risen to a record £1.7bn.