A government decision to allow tariff-free imports of thousands of tonnes of raw cane sugar could be "devastating" for East Anglia's sugar beet industry, warned farming leaders.

Ministers have confirmed that a new Autonomous Tariff Quota (ATQ) will be introduced for 260,000 tonnes of raw sugar coming into the UK from January 1.

The Department for International Trade (DIT) said it aimed to maintain preferential zero-tariff trade with poorer developing countries which produce sugar cane, while balancing support for UK growers and processors - who produce about half of the UK's sugar from beet grown mainly in East Anglia and the East Midlands.

But Fenland beet grower Michael Sly, who is chairman of the National Farmers' Union's sugar board, said the quota could allow imports of sugar produced in ways that would be illegal in the UK and could lead to the "permanent decline" of the home-grown sugar beet industry.

While farmers fear unfair competition, the DIT insists that food standards won't be compromised, the price of sugar will not be affected and the ATQ is "not likely to adversely impact sugar growers and the sugar refining industry".

Mr Sly said: “It is clear that the government has paid no attention to its own consultation and completely ignored the feedback from the home-grown sugar sector.

“The government claims that this quota will have no impact on UK beet growers as the sugar price will not be affected. This is clearly wrong.

"Sugar beet growers will undoubtedly be affected by this quota allowing imports of sugar produced in ways that would be illegal here."

Mr Sly said East Anglian sugar beet growers were already battling the effects of virus yellows, a crop disease carried by aphids which were previously controlled using neonicotinoid pesticides, which are banned in the UK, but not globally.

“We must be able to compete on a level playing field with growers elsewhere," he said.

“I would urge the government to rethink its decision on this quota and abandon its introduction, considering the devastating impact it could have on the thousands of sugar beet growers in the country.”

A DIT spokesman said: "As made clear in the government’s response to the consultation, we do not expect the proposed ATQ to have a material impact on the price of sugar.

"Evidence suggests that this ATQ is not likely to adversely impact sugar growers and the sugar refining industry."