The deputy prime minister, John Prescott, has said he regrets punching a protester after he was hit by an egg during a visit to Wales on Wednesday.

The deputy prime minister threw a punch before becoming involved in a violent scuffle after an egg was throw at him outside a rally in Rhyl in north Wales.

Prescott said he "deeply regretted" the event, but stressed he was acting in self defence. He described the confrontation as "frightening".

Tony Blair used Labour's morning press conference to defend his deputy.

"I have spoken to John Prescott last night and this morning. Of course he regrets the whole incident ever happened. He felt a blow on the side of his head and reacted instinctively. I think it is important in these next three weeks that we have a campaign in which there is a genuine dialogue and debate with people," he said.

Blair said the event was regrettable. He told reporters: "It would have been better if it had not happened...But John is John and you could have no better deputy."

The opposition parties have criticised Prescott, saying he should not have retaliated after being hit by an egg.

The local Conservative candidate said: "What sort of role model is he for young people? We don't want that kind of role model in Rhyl."

The protester, who was released on police bail after questioning, trapped Prescott against a wall before being pulled off by police and Labour Party minders.

A group of more than 30 angry protesters had gathered outside the theatre to protest over farming wages and to express their support for hunting.

"John Prescott was attacked by a protester as he made his way into a campaign event. He defended himself from the attack as anybody would in the circumstances," the spokesman added.