The government's target to clear the historic caseload of asylum applications will not be met and is being set back by a further backlog of cases, according to a Home Affairs Committee report.
In the MPs' last report before the general election, the committee said that far from being assured by the goverment it was increasingly concerned about action on the issue.
"Despite the assurances given by the Government in their responses to our original reports," the committee said, "the subsequent evidence we have received reinforces and, in some areas, increases the concerns we felt at the end of last year. None of these issues will be resolved within the next few months, and all will have a serious impact on thousands of people."
The report comes after an independent watchdog warned in February that the Home Office's target of dealing with 90% of asylum applications within six months was "unacheivable."
John Vine, the chief inspector of the UK Border Agency, also said the UKBA would have to more than double its work rate - from fewer than 5,000 cases to 11,000 a month - to clear around 200,000 outstanding asylum cases by July 2011.
Lin Homer, the UKBA's chief executive responded that "the UK Border Agency is concluding asylum cases faster than ever before, with the majority concluded within six months, down from an average of 22 months in 1997."
The government target in 2007 was to clear around 400,000 to 450,000 "legacy cases," - unresolved cases where a decision has been awaited for more than six months, with some dating back a decade or more.
The scale of the issue came into sharp political focus in 2006 when the then home secretary, Charles Clarke, was forced to admit that foreign ex-offenders had been released from prison without being considered for deportation.
Last year the National Audit Office revealed that only 5% of pre-2006 "legacy cases" had been deported.
The Home Affairs Committee said that post-election, the government - new or old - would need to approach the issue with realistic proposals.
"The Chief Inspector of UKBA has confirmed our fears that the historic caseload of asylum applications will not be cleared by the deadline and that a new backlog of cases is growing up. We look forward to the UKBA presenting our successors with clear, realistic proposals for dealing with both these problems, even if that means an acknowledgement that current targets cannot be met," the committee said.
The MPs' report also blamed "slow progress" in discussions between maritime and rail sectors on the e-border project and practical problems - technical and physical (such as an inability to send data) for the aviation industry for setting back the e-borders programme.
It added: "We note the Government's strongly-held view that the e-Borders project is vital to the security of the UK's borders, in terms of combating illegal immigration, serious crime and terrorism. This being so, the fact that so many major difficulties with the programme remain to be resolved causes us serious concern.
"We recommend our successors to keep a close watching brief on this programme."