On Saturday, high-profile Conservatives outlined proposals for a post-Brexit system of permits for workers from the EU. Many of the 52 percent of Britons who voted to Brexit cited concerns about immigration from EU countries.
"The best system is a work permits system with caps on numbers," one of the authors of the work permits plan, former works and pensions minister Iain Duncan Smith told BBC radio.
"It's implemented very strongly at the lower end of low skilled work which is where most of the difficulties and problems have been and at the upper end... you have a very light-touch process that allows people to come and go," he added.
But business leaders have expressed concern d about a so-called "hard Brexit" involving immigration caps and an exit from the single market that allows goods and services to move freely within the EU without trade barriers.
On Friday, car maker Nissan said that it would not push on with new investment in its Sunderland-based plant unless the government promised it would be compensated for any tariffs imposed by the EU.
According to the BBC, the Sunderland plant is Nissan's biggest factory in Europe, producing a third of the U.K.'s car output, and Nissan is due to decide early next year where to build its new Qashqai SUV. Nissan CEO Carlos Ghosn told the state broadcaster that the plant could "lose competitiveness" if U.K.-based companies had to pay a 10 percent tariff to import goods into the EU.
- Reuters contributed to this report.
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