Mr Jameson alleged that following the killing in the early hours of July 13, Kelly went back to Miss Nugent’s Mirfield home and told her that Mr Driver was dead.

The court heard that Miss Nugent laughed initially but Kelly repeated that Mr Driver was dead and added: “I went back to make sure.”

“She asked him if he was having a laugh and the defendant said ‘I’ve stabbed him’,” Mr Jameson told the court.

Kelly allegedly told Miss Nugent that he had stabbed Mr Driver in the chest and stomach and the jury heard that a postmortem examination of his body revealed 10 stab wounds to the chest and one to the abdomen.

Mr Jameson said Miss Nugent agonised over what to do following Kelly’s comments and it was not until about 40 hours after the killing that she and a neighbour of Mr Driver’s visited his home and found his body.

No murder weapon was ever found, but the neighbour noticed that a hunting style knife which had been on display in the flat was no longer there.

Mr Jameson alleged that a cigarette butt found on the doorstep of the flat had Kelly’s DNA on it.

The court heard that a few hours before his arrest, Kelly allegedly confessed to killing Mr Driver during a conversation with Miss Nugent’s mother, Carolyn Morgan.

Mrs Morgan knew about the killing because she had spoken to her daughter and when she asked Kelly what he had done he allegedly replied: “Carolyn, if you knew what he said to me you’d know why I did it.”

Kelly claimed that Mr Driver had told him that Miss Nugent was not his wife and never would be and had suggested that there had been some kind of sexual touching between them in his bedroom at the flat.

Kelly, of Abbey Road, has denied the murder charge and his trial is due to last about two weeks.