Calls have been made for an immigration detention cap to be introduced that will restrict the holding of detainees to a maximum of 28 days.
The recommendations for a detention cap are highlighted in a report, produced by a cross-party group of MPs and peers, which suggests Home Office officials are "failing to follow guidance" on using immigration detention sparingly and for the shortest period possible.
Conservative MP David Burrowes, a member of the All Party Parliamentary Group on refugees and on migration (APPG) who produced the report, said an "urgent rethink" of the current detention system was needed.
He said: "The lack of a time limit is resulting in people being locked up for months and, in some cases, several years purely for administrative reasons.
"While there is a need to properly control our borders, people who arrive by fair means or foul must also be treated with dignity and respect throughout the immigration process."
Currently the UK is the only EU country not to have an upper time limit on detention, a factor which the APPG suggest has "significant mental health costs" for detainees.
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