The Deputy Prime Minister will say in a speech today that visa "overstayers" are one of the biggest challenges faced by the immigration system:
As people travel more, for work, for holidays, you have more people coming into the country for temporary periods and so you need to find ways to make sure they leave.
The challenge isn't just stopping people coming into Britain illegally, it's about dealing with individuals who come over legitimately, but then become illegal once they're already here.
Earlier this month Shadow Home Secretary Yvette Cooper called for an end to student visitor visa loopholes, as the party repositioned itself on immigration.
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