Immigrants to pay cash bonds to ensure they leave

Sarah Coles
Nick Clegg
Nick Clegg

Nick Clegg has outlined some radical reforms to immigration this morning. Among them is a proposal that people travelling to the UK from outside the EU to work or study on a temporary basis will have to pay over a cash lump sum. They'll only get it back when they leave.

So why is the government doing this, and who will it affect?