Tesco’s former chief executive Sir Terry Leahy has said he is “very disappointed” with the grocery giant’s performance.

Leahy told Sky News: “As a shareholder I am very disappointed. I know the business will be disappointed and the board will be keen to take whatever action is necessary in order to improve the situation.

Tesco is a great business. And it’s a great employer and we need to see it back with confidence and growing again.”

Last week Tesco reported its worst quarterly performance in 40 years after like-for-like sales excluding petrol fell 3.7% in its first quarter to May 24.

Tesco’s current chief executive, Philip Clarke, took charge of the business in March 2011 and remains confident in its strategy.

When he revealed the performance Clarke said: “I don’t think we can go any quicker. We’re going at full pelt. Never before have we attempted to refresh 650 stores in a year, it’s a big change. If we try to go any faster, we’ll risk it.”