Thorntons’ problems can be traced back to its Derbyshire factory, which needs “a fundamental restructuring” to return the confectioner to health, according to former CEO Peter Burdon.

Burdon, who ran Thorntons for six years until 2006, said the current plant was unable to make the innovative products it needed to be competitive.

“The current facilities are not set up to do upmarket, Hotel Chocolat-style products, but neither do they do mass-market products well enough,” he argued.

The first priority should be to get the products right, rather than refurbish stores, he said: “People don’t go into the shops for the store environment, they go for the products.”

The extent to which Thorntons sought sales through other retailers was damaging to its own stores and the brand, he added: “It saddens me to see Thorntons being sold in run-down forecourts.”

During Burdon’s time as CEO, the confectioner began selling chocolates outside its own retail network for the first time. It now generates 40% of its sales through supermarkets and other retailers.

Burdon said he left because he disagreed with chairman John von Spreckelsen over the wisdom of this strategy.

Former chairman and founding family member Peter Thornton has also criticised its strategy, warning last month that if it were maintained “disaster is inevitable”.

In its latest results, Thorntons reported that profits had slumped from £8.4m to £3.1m in the six months to 7 January.