Liberal Democrat leader Nick Clegg is to call for a bail-like system of security bonds to tackle visa abuse in his first speech on immigration as deputy prime minister.
The bonds would be paid as a cash guarantee from visa applicants coming from high-risk countries and would be repaid once the visitor leaves Britain.
Mr Clegg will unveil the radical proposal as he outlines his vision for a "tolerant Britain, zero-tolerant of abuse" at liberal think-tank the Centre Forum.
The deputy prime minister will pledge to "lay the foundations for an immigration system that embodies this nation's instincts and its values" as he attacks the previous Labour government for "grossly" mismanaging the issue.
He will say: "We are grappling with the difficult challenges in our immigration system. Brick by brick, we are rebuilding it. Day by day we are making sure, quite simply, that it works. All the British people ask is for a system they can have confidence in. We hear that, and we are delivering it.
"I'm determined we lay the foundations for an immigration system that embodies this nation's instincts and its values - our openness and tolerance on one hand, our sense of fair play, on the other."
The deputy prime minister will say that visa "over-stayers" are one of the biggest challenges faced by the immigration system and the UK Border Agency (UKBA).
To tackle this issue, Mr Clegg has asked the Home Office to run a pilot of so-called security bonds, which echoes an Australian system applied to family visas. It is understood the cost of the bonds would vary but are likely to be in the region of four figures.
Mr Clegg will be seeking views on the proposal, including from the Home Affairs Select Committee.
He says: "The bonds would need to be well targeted - so that they don't unfairly discriminate against particular groups. The amounts would need to be proportionate - we mustn't penalise legitimate visa applicants who will struggle to get hold of the money."