The asylum system is supposed to take a strict stance against those who are caught living in the UK illegally.
But fewer than one in five of those who claimed asylum only after they were caught living here without permission have been kicked out.
Incredibly, more are being given permission to stay than are being removed.
Critics said the figures showed how the previous Labour government had turned Britain into a ‘soft touch’ for illegal immigrants.
In the past three years alone, only 7,294 of the 40,000 who claimed asylum after being caught breaking immigration rules were kicked out.
This compared with 9,869 - one in four - who were told they could stay. The remainder have either yet to have their cases decided or have dropped out of the system.
Sir Andrew Green, chairman of MigrationWatch, said: ‘These are astonishing figures.
‘These people entered illegally in the first place without bothering to claim asylum, so they can hardly be prime candidates.
‘Despite that, a quarter of them were granted some sort of protection.
‘Worse still, of all those detected, less than one in five have actually been removed. No wonder Britain is considered a soft touch and people are queuing in Calais to get here.’
The Home Office figures, obtained by Tory MP Priti Patel, detail what happens to people who are caught living in Britain illegally.
They can be caught trying to enter the country in the back of lorries, or using other clandestine methods. Alternatively, they may have entered legally then overstayed their visas.
Both categories are entitled to claim asylum when they are picked up by the authorities. However, the UK Border Agency is instructed to take a dim view of anybody caught in these circumstances.
Normally, there is a suspicion that anybody who does not claim asylum within a short time of entering the country may not be a genuine refugee.
One of the difficulties faced by the UK Border Agency is having enough staff to track down failed asylum seekers once they have been ordered to leave.
Must try harder: One of the difficulties faced by the UK Border Agency is having enough staff to track down failed asylum seekers once they have been ordered to leave
The UKBA is preparing to axe 5,000 jobs over the next four years. This has led to concerns there will be even fewer staff dedicated to asylum removals.
In a blistering report published last February, the Parliamentary ombudsman laid the blame at the door of the last government.
Ann Abraham said Labour was a ‘very long way’ from running a fast and fair immigration system that deports foreigners with no right to live here.
She found delays and incompetence at almost every level of the asylum and immigration process - with backlogs running to hundreds of thousands of cases.
The ombudsman warned the situation is such a shambles that illegal immigrants could soon benefit from an obscure rule which says those who avoid removal for 14 years can apply to stay here permanently.