A man who threw a foam pie at Rupert Murdoch has been convicted of assault and causing harassment, alarm or distress.

Jonathan May-Bowles, 26, from Windsor, launched the attack as the 80-year-old gave evidence over the phone-hacking scandal at last week's House of Commons Culture, Media and Sport Committee hearing.

May-Bowles, also known as Jonnie Marbles, admitted the crime at Westminster magistrates court.

The aspiring comedian, who had been sitting at the back of the room during Murdoch and his son James's evidence, was seen to get up and walk around the left side of the packed room to get to where the media mogul was sitting. He threw a paper plate with white foam piled on top at Murdoch's face

Murdoch's wife, Wendi Deng, leapt to her husband's defence, first slapping May-Bowles away and then throwing the plate at him as he was led away by police.

The incident was condemned by audience members and MPs including the Commons Speaker, John Bercow, and May-Bowles was subsequently suspended from the Labour party.

The defendant stood in the dock and spoke only to confirm his name, age and address and plead guilty to the two charges.

He was supported in court by his father and a group of friends.

Rav Chodha, prosecuting, said that, on 19 July, May-Bowles made his way through the Wilson room in Portcullis House to attack the News Corporation boss and used threatening, abusive or insulting words and behaviour.

In a hearing which lasted only 15 minutes, the prosecutor added that Murdoch did not support the charge of assault.

The hearing was adjourned for pre-sentencing reports until 2 August, when will he return to court to be sentenced.

His solicitor, Raj Chada, asked district judge Daphne Wickham for another date as May-Bowles had booked a holiday with his family and young son.

Wickham was unmoved and said a warrant would be issued for his arrest if he did not turn up.

She said: "He is on bail for a serious offence which carries a risk of imprisonment.

"It's due process.

"He should have thought about this on the 19th of July when he committed these offences."

The part-time stand-up comic emerged from court and said: "I would just like to say this has been the most humble day of my life."