LONDON  - Britain plans to create up to 10 freeports to boost trade and manufacturing by cutting cost and bureaucracy after it leaves the European Union, the government said on Thursday.

Prime Minister Boris Johnson, who took office last month with a pledge to deliver Brexit by the end of October "no ifs or buts", promoted the idea of freeports during his campaign.

Ports and airports around the country will be able to bid to become one of the freeports, the government said, announcing it had created a new Freeports Advisory Panel, including tax and technology specialists, to help set them up.

Freeports, also sometimes known as free trade zones, are areas where imported goods can be held or processed free of customs duties before being exported again. They can also be used to import raw materials and make finished goods for export.

"We are exploring freeports as an innovative way to drive growth and support thousands of high-skilled jobs across the UK," Rishi Sunak, Chief Secretary to the Treasury, said in a statement.

"We will focus on those areas that could benefit the most, as we look to boost investment and opportunity for communities across the country."

Freeports could cut down on unnecessary checks and paperwork as well as having customs and tax benefits for firms, the government said, reducing costs and bureaucracy and encouraging manufacturing businesses to set up.

Teesport and the Port of Tyne in northeast England, Milford Haven in Wales and London Gateway are among those who have expressed an interest in becoming freeports, the government said.

Research by consultancy and construction firm Mace last year said creating seven freeports in the north of England could add 9 billion pounds ($10.8 billion) a year to Britain's GDP and create 150,000 jobs.

But the UK Trade Policy Observatory, run by the University of Sussex and Chatham House think-tank, has questioned this figure, saying much of it would just be redistributing economic activity from elsewhere in the country.

"Policy impact evaluations often suggest that the net benefit of free zones is limited," it said in a research paper earlier this year. "The US experience is not very illuminating: whilst there are many jobs in the U.S. Foreign-Trade Zones, there is little evidence of how many are net creations."

(Editing by Stephen Addison) ((kylie.maclellan@thomsonreuters.com; +44 207 542 0401; Reuters Messaging: kylie.maclellan.thomsonreuters.com@reuters.net))