LONDON--The U.K. government must seek "barrier-free" trading access to the European Union for British businesses, said the Confederation of British Industry, an employers' lobbying group, Wednesday, underscoring mounting concern in the business community over the country's withdrawal from the bloc.

The body, presenting its findings from a survey of companies in the U.K., said the government's talks to formally exit the bloc should be governed by principles that "every sector agrees should guide the U.K.'s negotiation with the EU," including a "barrier-free" trading relationship with the EU, a clear plan for regulation and access to labor.

"The government's planfor leaving the EU must address all these areas, and be as smooth as possible," it said.

The CBI, which represents 190,000 businesses in the U.K, said the EU is the most important single trading partner for every major sector of the U.K. economy, with around 44% of U.K. products exported to the EU and 53% of U.K. imports from the EU.

Among the industries most affected by the U.K.'s trading relationship with the EU, says the CBI, are manufacturers with cross-border supply chains in aerospace, automotive and life science. In addition, international investors in professional and business services, financial services and technology use the U.K. as a European headquarters, it said.

The CBI also said the U.K. government must provide a clearer vision on British businesses' future trading relationship with the EU.

"The U.K.'s reputation as a place to do business relies on regulatory clarity and stability," it said.

The pound's devaluation since the June vote to leave the EU has roiled costs for U.K.-based businesses. Business and consumer economic indicators for the country have mostly navigated a calm course, but the Bank of England forecasts rising inflation next year and says the economy will slow amid negative business sentiment.

The U.K. government is planning to kick off the country's exit process by the end of March next year. The discussion will center on the U.K.'s access to a tariff-free single market and free movement of labor.

Prime Minister Theresa May said it would do the country a disservice to provide a "running commentary" on the government's negotiating position, but she said the government would provide more detail ahead of the talks.

A spokesperson for Mrs. May wasn't immediately available Wednesday to comment on the CBI's statement.

Write to Simon Zekaria at simon.zekaria@wsj.com

(END) Dow Jones Newswires

December 21, 2016 06:08 ET (11:08GMT)

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