Waitrose managing director Mark Price has revealed that the grocer has overtaken Marks & Spencer in food sales for the first time in its 105-year history.

Price said Waitrose passed Marks & Spencer in the first half of the year, achieving one of the John Lewis-owned grocer’s key internal targets. He said: “We are going great guns in all parts of the business.”

Price said internal Waitrose figures using data from TNS Worldpanel and Nielsen showed that Waitrose’s market share by sales is 4.2 per cent, while Marks & Spencer’s is 3.7 per cent.

Waitrose reported a record week’s sales – excluding Easter and Christmas – in the week to July 4, when they rose 13.3 per cent.

Price said developments such as the launch of its Essential value line, expansion in convenience and Waitrose Deliver helped keep up sales momentum.

“For some it is an inconvenient truth that Waitrose is growing as it doesn’t tie in with the times we are living in, but we have constantly been innovating and that has kept us ahead,” maintained Price.

An Marks & Spencer spokeswoman acknowledged that Waitrose is ahead by some measurements but insisted: “When it comes to food market share it’s never a true like-for-like comparison.”