LONDON (Reuters) - A coalition of British industry groups and education bodies, worried by the prospect of Brexit worsening skills and labour shortages, has called for the next prime minister to relax proposed reforms of the immigration system.

FILE PHOTO: A migrant worker sorts lettuce on a farm in Kent, Britain July 24, 2017. Picture taken July 24, 2017. REUTERS/Neil Hall

The #FullStrength campaign said on Wednesday it had written to both Boris Johnson, frontrunner to be the next leader of the Conservative Party and prime minister, and his rival, foreign minister Jeremy Hunt, calling for the government they would lead to lower the salary threshold proposed in draft immigration legislation from 30,000 pounds to 20,000.

In December, Britain set out in a policy paper the biggest overhaul of its immigration policy in decades, ending special treatment for European Union nationals.

Concern about the social and economic impact of immigration helped drive Britain’s 2016 referendum vote to leave the EU.

#FullStrength brings together bodies including London First, techUK, the British Retail Consortium, the Recruitment & Employment Confederation, UKHospitality, the Federation of Master Builders and Universities UK. Collectively they represent tens of thousands of businesses and employ millions of workers across all sectors and regions of Britain.

Their joint letter said more than 60% of all jobs in the UK currently fall under the proposed 30,000-pound salary threshold, highlighting the risk in setting the future level too high for vital services such as health and social care.

The coalition also wants the government to extend the temporary work route for overseas workers from one year to two years, revise the sponsorship model to make it easier for firms of all sizes to bring in the overseas talent they need, and reinstate the two-year, post-study visa for international students to work in Britain post-graduation.

“Without the ability to access international talent, many of our world-class sectors are at significant risk,” the joint letter said.

“As the UK prepares to leave the EU in the near future, it is imperative that the government puts in place measures that will avoid employers facing a cliff-edge in recruitment, and works towards building a successful economy that is open and attractive.”

Johnson has pledged that Britain will leave the EU with or without a transition deal on Oct. 31 if he becomes prime minister, while Hunt has said that he would, if absolutely necessary, go for a no-deal Brexit.

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