A new blueprint to end low-skilled migration after Brexit has been backed by senior Conservatives including former Tory leader Iain Duncan Smith.

The new system, outlined in the pro-Brexit Leave Means Leave report, would cut immigration to mid-1990s levels when between 55,000 and 77,000 more people came to the UK than left. Last year the number was estimated to be 246,000.

Low skilled workers from Europe would be banned and a work permit system introduced for graduate-level jobs. To combat the farming industry’s fears about crops rotting in fields due to lack of workers, 25,000 agricultural workers could apply for a six month permit.

Tourists and students from the EU would be able to come to the UK on holiday or to study without a visa and those already living in the the UK could apply for citizenship after five years. The report said: ‘There is no doubt that profound concern about the level of net migration to the UK and its impact on the population, housing and public services was a key driver of the vote to leave.

‘If the result of the referendum is to be honoured in spirit and letter, free movement of people from the EU to the UK must come to an end.’

Former Work and Pensions Secretary Mr Duncan Smith said: ‘This is a sensible set of proposals for a future immigration policy that the Government should adopt.

‘It would deliver on the Brexit mandate both to take back control of borders and bring down net levels of migration.’

The paper said ministers should put greater emphasis on training unemployed people to take up semi-skilled and trade occupations, filling roles currently taken up by EU migrants.

However, pro-European business leaders and MPs warned slashing the number of immigrants would further slow down the UK economy.

Pat McFadden MP, leading supporter of Open Britain, said: ‘Even after the UK leaves the European Union, our country will still need the energy, drive and commitment that immigrants from Europe and around the world bring to Britain.’