A partially-sighted Clayhall man is demanding answers after being wrongly told he was not allowed to take his guide dog into a supermarket three times.

Gary Mazin, 40, was shopping at Sainsbury’s in Cranbrook Road, Gants Hill, on Thursday when a member of staff allegedly approached him and said “no dogs allowed”.

Mr Mazin, who had the dog on a high visibility harness, said the same man had stopped him in the shop six months before.

He was also challenged by a security guard last year.

The father of two, of Stradbroke Grove, said: “It was the final straw, I was really upset.

“Supermarkets are never the best places to get around and I don’t need that.

“There’s such an obvious difference between a guide dog and a pet – I don’t understand how it happened a third time in the same shop.”

Mr Mazin, who works from home as a recruitment consultant, also runs guide dog awareness sessions in schools.

He said small shops are often unaware of disabled access laws but large retailers are expected to train staff.

Mr Mazin added: “It’s 2013 and the fact people in a big organisation are telling people guide dogs are not allowed is ridiculous.

“It’s just common sense and it shouldn’t be an issue.”

The 2004 Disability Discrimination Act requires shops, restaurants and hotels to make “reasonable adjustments” to allow access for people with mobility difficulties.

David Kent, London engagement co-ordinator for charity Guide Dogs, said the rejection of being told to leave a shop can be “heartbreaking”.

He added: “Sainsbury’s usually have a high standard of customer service and it’s not a common occurrence.

“But it’s unacceptable when guide dog owners are prevented from doing everyday things that most people take for granted.”

A Sainsbury’s spokesman said: “We’re very sorry about Mr Mazin’s experience in store, but we’re glad he brought it to our attention so we could make amends.

“We have reminded our colleagues about the policy to allow guide dogs in store and have offered Mr Mazin a goodwill gesture to say sorry.”

The supermarket is also donating £100 to a charity of his choice.