The National Autistic Society (NAS) is challenging a decision by the Driver and Vehicle Licensing Agency (DVLA) to force autistic people to inform them of their diagnosis even if it does not affect their driving.

The surprise change in policy – which was not communicated to any autistic people, charities or medical professionals – emerged after a person with autism contacted the NAS and told them the DVLA website said drivers must disclose if they have an autistic spectrum disorder.

Until recently, the website has simply said that drivers must tell the DVLA if they have an autistic spectrum disorder “and it affects your driving”. This is standard for many conditions. The final clause has been removed and is now in a separate paragraph warning of the risk of a £1,000 fine or possible prosecution if these drivers are involved in an accident.

The Labour MP Jess Phillips joined in with criticism of the decision and said she would take the matter further, tweeting: “Believe me when I say I will be asking the Equality and Human Rights Commission (EHRC) to look into this.”

Sophie Walker, the former leader of the Women’s Equality party – whose daughter is autistic – also called for the EHRC to investigate. “This is discrimination,” she said. “I’m furious. I am going to follow this up next week.”

An EHRC spokesperson said the body would expect any change in policy affecting people with an impairment to be clearly consulted on and communicated. “Failure to do so may be a breach of the public sector equality duty,” they said.

Jane Harris, the director of external affairs and social change at the NAS, said: “We are very concerned by the suggestion that people should inform the DVLA after being diagnosed as autistic.

“Autism is a lifelong disability and if someone has passed their driving test we can’t see how an autism diagnosis would change their ability to drive.

“We have contacted DVLA who have told us that the ‪‪gov.uk‬‬ online guidance was wrong previously and that autistic people should notify them of their diagnosis,” she said. “We are questioning the justification for this directly with them, as many of our supporters are very concerned as they were not previously aware that they needed to do this.

“We don’t believe that the DVLA guidance reflects the autism spectrum properly and are calling for the DVLA to make sure that no one is fined until this matter has been resolved.”

The DVLA said: “There have been no changes to autism spectrum disorder being a notifiable condition – this has been the case for a number of years. We have recently aligned the advice on our A–Z guide for the public with the advice for medical professionals.

“Notifying DVLA of a medical condition doesn’t mean a driver will automatically lose their licence. In fact more often than not they can continue to drive.

“We always keep our advice under review and work with our independent medical panels to do so.”

Despite that reassurance the change in policy has caused a great deal of anxiety in the autistic community.

Laura James, ambassador for the NAS, said: “We’re upset on a number of levels, but the lack of communication is horrifying as we’ve all potentially been driving illegally since they changed the rules.

“Also, we were all autistic when we passed our tests, which are obviously designed to test people’s skills and ensure they are safe to drive, so this change seems nonsensical.”

Informing the DVLA is not a simple process. The form asks questions that relate to substance abuse and psychiatric treatment but nothing about autism itself.

Drivers have to give information on their GP and specialist and, said James, “as most GPs have a very vague understanding of autism and most autistic adults don’t have a specialist, it is hugely worrying as many of us could lose our driving licences for essentially being different”.