After 12 years of tireless fund-raising and travelling the world as the charity's ambassador, Mr Parton has been told his services are no longer required at Canine Partners.

The 49-year-old, who is disabled, says he is disgusted by the decision and claims he has raised millions for the charity over the years.

The row comes after 'wonder dog' Endal retired in July because of his health and Mr Parton bought a new puppy to take over duties such as picking up washing and helping with the supermarket shopping.

The charity is upset that Mr Parton bought Endal Junior himself rather than it providing a replacement dog.

A letter signed by the chairman, David Newberry, said: 'The path that you have chosen will inevitably lead to a gradual disengagement of your relationship with the charity but given recent difficulties, this is likely to be for the best.'

The charity also refuses to allow Endal Junior to wear an official Canine Partners jacket, which shows people he is a working dog.

Mr Parton, of Walburton Way, Clanfield, can still take Endal Junior into stores. He says the jacket demonstrates he's not an everyday dog.

'I am really hurt,' he said.

'When Endal Junior was trained he would have been seen in public wearing one of the charity's jackets and been a great ambassador for them.

'You don't just grow a new head. I still have the head injury that caused me to forget getting married. I am still disabled.'

Bruce Jenkins, the acting chief executive of Canine Partners, said in a statement: 'Further to the retirement of Canine Partner Endal, as announced in July, Allen Parton chose to select his own puppy, EJ, independently of Canine Partners, with a view to training it himself. The charity has offered Allen advice and guidance to date and has been happy for him to participate in Canine Partners puppy classes with EJ alongside the charity's own youngsters – which he continues to do.'