Immigration should be devolved to Scotland as part of a fundamental reform of the current UK model, according to a think tank.

Russell Gunson, the head of think tank IPPR Scotland, urged the UK Government to overhauling the existing model as Britain prepares to exit the European Union (EU).

A report from the independent IPPR concluded the UK's current immigration system "lacks a strategic mission", with policy developed as a result of "ad hoc reactions to political and operational crises".

It called for a new immigration policy to be developed which would not focus on numbers but would rather link policy in the area with economic and social priorities.

The report, produced by the IPPR Commission on Economic Justice, said: "As the government reviews its policy over the coming 12 months in preparation for Brexit, there is a unique opportunity to put this strategy into practice and deliver an immigration system that meets, rather than hinders, our economic needs.

"A key tenet of the UK's future immigration strategy should be to develop greater geographical flexibility within the system, in order to help address the sustained and growing economic imbalances across the UK's nations and regions."

The think tank accepted this would be "a major shift in immigration policy".

Mr Gunson said: "Scotland has specific challenges that the current UK-wide immigration system is failing to address.

"With an ageing population and the need to boost our economy through innovation and productivity improvements, a devolved immigration system across the UK is an idea whose time has come."

He claimed Scotland has some of the lowest levels of opposition to immigration in the UK.

Mr Gunson added: "Devolving immigration could allow areas in the UK to be much more responsive to their local economic needs and public opinion, improving integration, trust and ensuring consent for immigration.

"As the Brexit negotiations continue, the UK Government should consider fundamental reform of our immigration system, devolving immigration to Scotland and other parts of the UK."

A Scottish Government spokesman said: "We welcome this report from the IPPR, which argues that Scotland should be able to set its own labour immigration rules to meet our unique economic and demographic needs

"It is clear that the one-size-fits-all approach to immigration policy in the UK is not right for Scotland.

"This report adds to the growing consensus about the need for a tailored approach to immigration to meet the needs of different parts of the UK."

The spokesman said inward immigration brings huge benefits.

He added: "Businesses big and small, the agriculture sector, financial services companies and our NHS rely on migrant workers who perform vital roles in our economy, ensuring an available pool of labour to meet employers' needs, across all sectors and skill levels."

A Home Office spokeswoman said: "After we leave the EU, we will put in place an immigration system which works in the best interests of the whole of the UK.

"As part of our work to develop this system, we have asked the independent Migration Advisory Committee to assess the economic and social impact of EU citizens in all parts of the UK.

"We are carefully considering the options for the future immigration system and will set out our plans later this year."