British international schools have been told they can no longer request standard or enhanced criminal records checks for teachers they wish to recruit.
The Council of British International Schools (COBIS) has historically processed Disclosure and Barring Service (DBS) checks on behalf of its members.
But the DBS has said that this is unlawful and must stop, because checks can only be made on behalf of organisations based in England or Wales.
COBIS chief executive officer Colin Bell described the news as "disappointing" in a message to members.
DBS checks for schools 'put safety first'
He added: "COBIS is committed to reducing risk to children and people worldwide, Therefore, the association is frustrated that the UK Home Office can no longer offer this vital service, which puts safety first, to British schools overseas."
Mr Bell passed on to his members a notification that the Department for Education sent to all DfE-approved BSO (British Schools Overseas) inspectorates and to all UK and overseas associations.
It says that such organisations "can apply for a basic DBS check if they wish (which gives convictions that are not spent), and they can access information through an International Child Protection Certificate, obtained through ACRO".
Mr Bell's message says he has lobbied the Foreign Office; the Department for International Development; the British Council; ACRO, which has joint responsibility for the administration of the International Child Protection Certificate (ICPC); and the child protection and education leads at Unicef.
Tes understands that the clampdown has not come about due to a change in the law, but due to a decision to tighten compliance with existing legislation.
A DBS spokesperson said: “The legislation governing DBS checks has not changed. In order to receive an enhanced or standard disclosure check, the application must be for an eligible role.
"In addition, the recruiting organisation must be based in, and the recruitment decision made in, either England or Wales.”
The DfE referred Tes to the Home Office for comment. The Home Office did not provide a comment.
