Nearly 30,000 bottles of Strathmore mineral water have been withdrawn from sale in the UK after some were found to contain mould.

The alert came after the substance was found in a number of plastic bottles of Strathmore still mineral water on sale at UK cash-and-carry chain Costco.

The affected products involve bottles produced between the end of July and the end of August. Strathmore's owner, AG Barr, said a faulty filter had caused the problem. The filter, the company said, has since been replaced.

"We have also consulted fully with the Food Standards Agency regarding the affected stock and they are happy with the action we've taken," the company said.

"This issue was in no way harmful to health, as verified by independent experts and was purely a cosmetic problem."

AG Barr, which also produces Irn-Bru, said it has taken "all possible steps" at the Strathmore factory in Scotland "to prevent this issue from happening again."

AG Barr bought Strathmore from US drinks giant Constellation Brands for GBP15m (US$28.1m) in May.