The last decade has seen the number of foreign offenders locked up every year in English prisons more than double, with only a few actually completing their full sentences.
With the majority of them guilty of serious crimes, receiving sentences of four years or more.
Official figures show the number of European offenders sent to jail for violent or sexual offences has tripled in recent years.
Despite there being a scheme in place to repatriate foreign offenders for some time, only 10 have been sent back in the last few months under existing arrangements.
The statistics were uncovered in parliament by Lib Dem MP Martin Horwood, who sits on his party's international affairs committee.
Horwood said that Britain could save millions by returning offenders to their home countries under the new scheme. The cost of keeping one prisoner locked up for a year is more than £30,000. Read More