Secretary of State for Work and Pensions Iain Duncan Smith explained "more robust" questioning for migrant benefit claimants would protect the integrity of the benefits system.
He said: "It is vitally important that we have strict rules in place to protect the integrity of our benefits system.
"The British public are rightly concerned that migrants should contribute to this country and not be drawn here by the attractiveness of our benefits system. And we are taking action to ensure that that is the case.
"The roll-out of the new habitual residence test is the first in a series of measures to ensure that we have a fair system - one which provides support for genuine workers and jobseekers, but does not allow people to come to our country and take advantage.
"It is a crucial part of our long-term plan to secure Britain's economy."
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