A blind grandmother was refused entry to a Morrisons supermarket with her guide dog because of the shop manager's "severe pet allergies".
Caroline Kennelly, 54, was left on the verge of tears following the incident in Wincheap, Kent, last Thursday.
Under equality law, Ms Kennelly has the right to enter all shops with Dougie, her assistance dog.
However, three signs in the store window warn that dogs are not allowed, with one referring to the manager's "severe pet allergies".
And while Morrisons bosses have claimed the incident "should not have happened", the local manager reportedly doubled down, insisting the store would continue to ban guide dogs.
Ms Kennelly, who has just 3 per cent of her vision because of a degenerative condition, said she hoped the Morrisons would be a safer store to visit as others required her to navigate busy traffic in Wincheap.
She said Dougie was in his full harness and working equipment when "the man behind the counter said, 'no dogs'.
"I said, 'No, I'm not leaving'. I stood there in disbelief. I'm saying to him, 'You are breaking the law. You are not allowed to deny me access here'. And he wouldn't listen.
"I was nearly in tears but I was trying to hold it together. You can stand your ground and say 'I'm not leaving', but inside you are in pieces because it's intimidating and it's discriminating.
"I wonder if I'm going to get another refusal somewhere else. It dents your confidence."
Eventually, a friend stepped in and was able to buy Ms Kennelly the things she needed.
The Equality and Human Rights Commission says employers should take reasonable steps to ensure that workers with allergies have minimal or no contact with dogs.
However it also adds: "Reasonable steps are unlikely to include banning all assistance dogs."
Ms Kennelly has been registered blind since 2003 as she has a disease called retinitis pigmentosa, which causes loss of vision. She was first diagnosed when she was 11 and now has been left with no peripheral vision.
She also cannot make out details further than a couple of feet away from her. She says having a guide dog has been a huge confidence boost.
"It sounds really cliche, but when I got Dougie six years ago, he changed my life," Ms Kennelly said. "He gave me back all my independence, to be able to go and do what I wanted to do, and just be my best mate really."
Morrisons apologised for the incident, with a spokesman for the supermarket chain saying: "Everyone is welcome at Morrisons and so we have followed up with the store directly as this should not have happened. We are also reaching out to the customer directly to apologise.
"The Morrisons Daily store in Canterbury is a franchise store and we are working closely with the team there to find a solution."
However, the shop's manager reiterated that Ms Kennelly would not be allowed in with Dougie because of the owner's allergies when approached by Kent Online.
They claimed that a staff member would do her shopping for her if requested.