A Marks & Spencer director has joked that the retailer’s eco kettles are “bug ugly” and said he feared his cleaner could accidentally leave it on and burn his house down.

Richard Gillies, director of Marks & Spencer’s green initiative Plan A, made the remark while speaking at the Prince of Wales-backed sustainability summit at Lancaster House.

According to the Daily Telegraph, he told a stunned audience that the retailer would need to come up with a “Plan B” for kettles.

“I have one of our ‘eco kettles’ because I kind of thought I should have one,” said Gillies. “But between you and me it’s bug ugly. It costs more, it’s bug ugly and it’s difficult to use,” he said.

“If the cleaner comes I’m frightened she will burn the house down because she doesn’t move the water from one chamber to the other.”

M&S has now discontinued the kettles, which sold for £29.95. They had featured in M&S’s first range of greener home products, launched by chairman Sir Stuart Rose three years ago.

Gillies said M&S had saved millions and begun to regain its “trusted” reputation among middle-class shoppers since launching Plan A in 2007.