Human trafficking and illegal immigration could be increasing as a result of tougher asylum controls, according to a Home Office report published yesterday.

Measures adopted by North European countries to deter asylum-seekers and economic migrants mean that southern European countries such as Italy, Greece and Spain, with their more vulnerable borders, are regarded as the main migration route into the EU.

"There is strong circumstantial evidence, though little authoritative research, that restrictionism...led to growing trafficking and illegal entry of both bona fide asylum-seekers and economic migrants," it said.