Nine Cumbrian hill farms are still banned from selling meat because of high radiation levels caused by the Chernobyl accident.

It is 21 years since the Ukrainian nuclear reactor exploded and spread a huge cloud of radioactive dust across western Europe. Government restrictions which were expected to last a few weeks are still in place more than two decades later.

The ban on selling meat into the food chain affects 11,500 sheep and lambs on nine sites, which are not identified in Government figures. Any lamb with a reading of 1,000 becquerels/kg cannot be sold for consumption.

The high levels of caesium-137 are largely found in upland flocks, which are tested in summer when levels are at a peak. A triangle of land south of Buttermere is thought to be the worst affected. More than 300 farms in Wales and 11 in Scotland are also subject to the same restrictions.

Nine tons of radioactive material were released in April 1986 from the power station’s reactor, which is 1,500 miles from Britain.