Up to half of British taxpayers’ cash meant for Syrian refugees has been wasted on United Nations red tape.

Instead of providing food, medicine and shelter in camps, much of our aid money is going on administration, overheads and staff costs.

And a UK official in the region told investigators the UN relief effort was ‘at best mediocre’.

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Up to half of British taxpayers’ cash meant for Syrian refugees has been wasted on United Nations red tape

Britain has given £1billion to help Syrians fleeing the twin menace of Islamic State and dictator Bashar Al-Assad. Dwarfing the donations of other European countries, it is the UK’s biggest ever response to a refugee crisis.

Around £600million has been handed to three UN bodies – the World Food Programme, children’s fund Unicef and refugee agency UNHCR.

But much of the cash is not accounted for, with Unicef failing even to give a breakdown. Shockingly, the UNHCR has spent £7million on its press office.

The BBC exposé is a blow to David Cameron who has been criticised for diverting 0.7 per cent of national income abroad.

And ministers have often highlighted the value of the camps in stopping refugees making the perilous journey to Europe.

‘It seems extraordinary amounts of money are being siphoned off for bureaucracy and overheads,’ said Andrew Rosindell, a Tory MP on the Commons foreign affairs committee. ‘If this is the case, it is very disappointing and we need to find out why this has been allowed to happen.’

Compassion: The Prime Minister's wife Samantha Cameron visits a refugee camp in Lebanon

The investigation by Radio 4’s File on Four programme found that a lack of financial transparency at the UN made it extremely difficult to discover how much was being spent and on what.

But in some instances, UNHCR projects received only around half of the money paid out by the Government. The rest went on staff, infrastucture, vehicles and hired contractors. The agency often contracts charities and other groups to carry out work on its behalf. These groups may then employ a local contractor.

Kilian Kleinschmidt, who ran the UNHCR Zaatari refugee camp in Jordan until a year ago, said aid money moved along a chain, starting with a major UN agency.

‘It’s possible even up to 50 per cent may go in that chain of transfer of funding,’ he said.

‘This is maybe acceptable and should be acceptable in times of emergencies – this is when you have to move fast.

‘But as fast as possible we have to change that to think how would you run, for instance, the water system in a city of 100,000 people. You don’t have these different layers – you would have a water company or a water provider.’

The UNHCR received £116million from the UK and the World Food Programme £227million.

But the only detailed WFP project budget available was a £16million breakdown for food vouchers for three months in 2012. It showed that 7 per cent, or about £1million, went on management fees for officials at WFP headquarters in Rome while another £2million went on staff costs.

Britain has given £1billion to help Syrians fleeing the twin menace of Islamic State and dictator Bashar Al-Assad

Earlier this year, the WFP warned it would have to cut its food aid because of falling budgets. Yet, globally the agency’s payments for staff soared from £450million to £550million.

Unicef was given £120million by Britain but there was no breakdown of how it was spent, said investigators.

Dorian LaGuardia, an academic who has studied UNHCR operations, said it was a struggle to uncover detailed information and staff made little effort to seek efficiencies.

He said the biggest issue was finding out what is ‘directly related to helping refugees and what is considered overheads, the costs of keeping the lights on in senior management’.

Mr LaGuardia’s research found up to 25 per cent of an aid project’s budget could go on overheads.

Andrew Harper, the head of the UNHCR in Jordan, said the 50 per cent claim was shocking.

He added: ‘If that was a figure then we need to address why it was so high.’ Abeer Etefa of the WFP said: ‘Over 90 per cent of the donor funding is going directly into the refugee vouchers.’

A Department for International Development spokesman said: ‘We have focused relentlessly on getting help where it is needed most and on doing so transparently, effectively and accountably. To suggest otherwise is both misleading and wrong.’

An estimated 12 million people have fled the Syrian civil war and yesterday it emerged that a record 218,000 migrants crossed the Mediterranean to get to Europe last month.