Prime Minister David Cameron's official spokesman said:
The report raises legitimate concerns about the backlog of outstanding cases. We are aware of that problem. It is something we are already trying to tackle.
The report itself acknowledges that we have started to address some of these problems.
Asked whether there might be an amnesty for people in the backlog, the spokesman said: "That is not something we are considering."
The Home Affairs committee report said the UK Border Agency backlog of more than 275,000 included:
- At least 150,000 migrants who have been refused permission to stay in the UK
- 21,000 asylum cases
- 3,900 foreign offenders living in the community
- A further 57 foreign criminals who were released in 2006 without being considered for deportation have not yet been traced
And the so-called 'controlled archive', used for cases where the agency has lost track of the applicant, contains 80,000 asylum applications and 21,500 immigration cases, the report said.
The Home Affairs committee report - which looks at the UK Border Agency's work between December last year and March - also called for the agency to make all its inspections of colleges unannounced, rather than giving them advance notice so key people and documents can be ready.
"If we are to eliminate bogus colleges from the education landscape and employers that abuse the immigration system then visits will have to be unannounced, robust and thorough," it said.
The latest damning report on the UK Border Agency's work has also said the Home Affairs committee did not believe the Government's aim of cutting the 260,000 student visas issued each year by a quarter would benefit the UK.
Students should be excluded from the net migration figures instead, it said.
Britain would then continue to attract international students, a market worth £7.9 billion, and still be able to aim to meet David Cameron's pledge to cut net migration from 250,000 to the tens of thousands by 2015, the report said.
Keith Vaz, the committee's chairman, said the backlog, which will take years to clear, was unacceptable, adding that the agency seems to have "acquired its own Bermuda triangle".
It's easy to get in, but near impossible to keep track of anyone, let alone get them out. This is the first time that the committee has collated all the cases at the UK Border Agency that await resolution. This backlog is now equivalent to the entire population of Newcastle upon Tyne.
The troubled UK Border Agency faces a backlog of more than 200,000 cases - the equivalent to the population of Newcastle - MPs have warned.
Missing foreign criminals, failed asylum seekers, illegal immigrants and others refusing to leave the country make up more than 275,000 cases, which the agency still needs to deal with, the Commons Home Affairs Select Committee said.