Former immigration minister Damian Green has dismissed the Leave campaign's suggestion that a points-based immigration system would be better for the economy.
While members of the European Union currently have no restriction on travelling to Britain, the country already uses an 'Australian-style' points-based system to assess people from outside the EU planning to work in the UK.
Prominent 'Vote Leave' politicians such as Michael Gove and Boris Johnson have called for a similar system to be put in place for all migrants, claiming that free movement has affected wages and placed strain on public services in the UK.
The system would, they say, allow greater control of those coming into the country and allow immigration to be restricted to those considered to be of "high value" to Britain.
But speaking on behalf of the Remain campaign, Green claimed there are "two big things wrong" with the proposed method of managing migration.
"The first thing is that an Australian-style points-based system is actually designed to increase immigration," the MP for Ashford told Julia Hartley-Brewer.
"Immigration into Australia is twice the level per head of population as into the UK. So it doesn't meet the needs the Leave campaign have identified."
Using the example of Norway, who are not members of the EU but who have signed up to be part of the single market and trade freely with members of the Union, the MP for Ashford added: "The second [problem] is that if we instituted this, we would absolutely have to leave the single market because EU rules state you have to have freedom of movement.
"Plenty of experts agree that being outside the single market would be the main reason why leaving the EU would cause huge economic damage.
"So this fails on those two basic tests."