EU nationals should be subject to the same rules as migrants from the rest of the world after free movement ceases to apply in Britain, a UK Government-commissioned report says today.

The long-awaited study also concluded that the post-Brexit immigration system should make it easier for higher-skilled workers to come to the country while continuing to limit access for those in lower-skilled roles.

UK Ministers asked experts to carry out an in-depth analysis on the patterns and impact of migration from the European Economic Area in July last year to help them draw up proposed new rules for after the implementation or transition period ends in December 2020.

Theresa May is expected to use the subject of immigration as the centre-piece to her keynote speech to the Conservative Party conference in two weeks’ time.

The Migration Advisory Committee's[MAC] final report says that, if immigration is not part of the negotiations with the EU and the UK is deciding its future system in isolation, there should be no preference given to EU citizens.

"A migrant's impact depends on factors such as their skills, employment, age and use of public services, and not fundamentally on their nationality," the report says.

The committee emphasised that it was not expressing a view on whether or not immigration should be part of the Brexit negotiations.

Professor Alan Manning, the MAC Chairman, said: "If - and this is not an MAC recommendation - immigration is not to be part of the negotiations with the EU and the UK is deciding its future migration system in isolation, we recommend moving to a system in which all migration is managed with no preferential access to EU citizens."

This would mean ending free movement but that would not make the UK unusual, he said, citing Canada's approach as an example.

Prof Manning added: "The problem with free movement is that it leaves migration to the UK solely up to migrants and UK residents have no control over the level and mix of migration."

The review also suggests the future immigration policy should favour high-skilled workers as there is clear evidence they bring benefits to the UK's public finances, innovation and productivity.

But in a finding that is likely to spark opposition from some sectors, the MAC concludes that there is no need for a specific migration route for low-skilled work with the possible exception of a seasonal agricultural scheme.

The report recommends that a cap on the number of Tier 2 skilled work visas should be scrapped and the scheme opened up to migrants in medium-skilled posts.

"Our recommendations to the Government on a future work immigration system post-implementation period are designed to benefit the resident UK population," said Prof Manning.

Labour’s Diane Abbott urged the Conservative Government not to ignore the MAC report.

She said: “Labour has said that our immigration policy needs to be based on our economic needs while meeting our legal obligations and treating people fairly; which means ending the discrimination against non-EU migrants, especially from the Commonwealth.

“This is not what we get from the Tories; the party of bargaining chips, Go Home vans, and the hostile environment.”

A Home Office spokesman said: “After we leave the EU, we will take back control of our borders and put in place an immigration system that works in the interests of the whole of the UK.

"We commissioned this report in addition to our engagement with business to better understand the impact of EU citizens on the UK labour market. The Government is clear that EU citizens play an important and positive role in our economy and society and we want that to continue after we leave.

“We will carefully consider the MAC’s recommendations before setting out further detail on the UK’s future immigration system,” he added.

The Government will introduce its new immigration policy from 2021 once the implementation period ends.

In its White Paper on the UK’s future partnership with the EU, it set out how it wanted to agree a “framework for mobility,” which would support businesses to provide services and move workers between the UK and the EU.

Under the EU Settlement Scheme EU citizens will only need to complete three key steps to maintain their citizenship status in the UK: prove their identity; show that they live in the UK and declare any criminal convictions.