Former Marks & Spencer boss Lord Stuart Rose has lambasted Mike Ashley over his plans to create a UK retail high street “oligopoly”, and said the sector is still too focused on bricks and mortar.

The chair of several retailers, including online grocer Ocado, Lord Rose said he would “think twice” about focusing purely on bricks-and-mortar retail, given the shift towards online that is taking place at the moment, according to

“My view in retail is to stay nimble, lean and mean. You need to be able to turn on a sixpence,” said Rose. “I wouldn’t want to lock myself into anything that’s not flexible – we’re operating in a fast-moving world.”

Rose also said that Ashley’s failure to buy ailing department store chain Debenhams, following a protracted and public battle, might actually prove a blessing in disguise. The Fat Face and Oasis chair described Debenhams as having “always been behind the curve”.

“What we’ve still got in most sectors in the UK is too much capacity in terms of bricks and mortar,” he said.

“Unless you’ve got a really strong brand or unique selling point, you’re going to find you’re squeezed. That’s why the Debenhams of this world are struggling, that’s why BHS disappeared.”

Rose also said that he played no direct role in brokering the February joint venture tie-up between M&S and Ocado, but declared the deal would prove a “winner” for his former business.