The jury in the trial of a man accused of murdering his stepfather heard defendent's claim his mother was the real killer.

Rachid Riahi is accused of stabbing his stepfather, 49-year-old Kevin Francis, to death on October 6 last year.

Mr Francis was pronounced dead at his house at 9.30pm, having received an 11cm deep knife wound to the chest, which went through a rib and pierced his heart.

But Raana Sheikh, representing Mr Riahi, told the Old Bailey jury on Monday that the defendent claimed his mother had killed Mr Francis.

"The bulk of the evidence rests squarely on the shoulders of Julia Francis," she told the court.

"All we've heard is circumstantial evidence.

"Consider who had the means, motive and malice?

"Who was cold hearted and cunning enough to commit this offence?"

Last week, Mrs Francis told the court she had left the house on October 6 to use a nearby phone box to call one of her daughters.

They had no landline and she claimed her mobile phone had no credit, the court heard.

When she returned she had found her husband dying in the arms of Mr Riahi.

Miss Sheikh told the court: "We're saying firmly, when Mrs Francis left the house, Kevin was already on the floor, slumped in the kitchen.

"Something must have happened in the kitchen and she plunged a knife into his chest.

"You heard what she wanted was for Mr Francis to get out of her life and for him to never come back.

"She wanted her grandkids to live in the house and he wasn’t allowing it."

Prosecutor Wayne Cleaver told the court the clothes Mrs Francis wore on the day her husband died had shown know traces of blood on them.

He told the jury: "All the evidence points towards Rachid Riahi striking the fatal blow with the knife. He remains the prime suspect."

The trial continues.