Pakistan's High Commissioner to the UK has said not enough is being done to carry out security checks on foreign students.
It comes after it emerged that most of those held after the terror raids in the north-west of England were in Britain on student visas.
Wajid Shamsul Hasan said Pakistani authorities could help carry out background checks on student visa applicants but were not allowed to.
He said: "It is at your end, you have to do something more."
Ten of the 12 arrested in the raids across the North West - including at Liverpool's John Moores University - were Pakistani nationals.
Shadow home secretary Chris Grayling called for the Government to "urgently step up" background checks on students coming to Britain from countries linked to terror.
Government figures showed 42,292 student visas were issued to Pakistani students between April 2004 and April 2008. In 2007/8, the last financial year for which figures are available, 9,544 Pakistani nationals were given student visas. Figures from 2006 showed 98% of applications for extension of leave to remain in Britain were granted and only 2% were rejected.
A Home Office spokesman said all students applying to come to Britain are checked against terror "watch lists".
Sir Andrew Green, chairman of campaign group Migrationwatch UK, said student visas were a "gaping hole" in Britain's borders.
Immigration minister Phil Woolas said fake colleges were the "biggest loophole" in the immigration system.
