A jeweller told a psychiatrist following his alleged murder of his partner that he wanted to kill her because he was terrified she would leave him for "some rich guy", a court heard.

Ian Levy, 54, was arrested after stabbing girlfriend Elize Stevens, 50, more than 80 times as she screamed for her life.

He denies murder by reason of diminished responsibility.

Prosecutor Jane Bickerstaff QC told the Old Bailey in her closing speech how Levy made an "impulsive confession" to a psychiatrist saying he had planned to kill Ms Stevens and then take his own life after she invited him to accompany her to a friend’s 60th birthday party.

He added that he was terrified she would meet someone else there and end up leaving him.

"He makes it clear that this was premeditated, that he was afraid she would met someone else, 'some rich guy'", the prosecutor continued.

"He told one of his doctors, 'I did not want her to meet someone else. I knew if I carried on I couldn’t maintain the relationship but if I ended it I would kill myself'."

Ms Bickerstaff told jurors: "It was him or her. He thought about it for a few days and took an opening and did it.

"He had thought of killing her then himself for a few days.

"That is completely premeditated, that is a decision he took to end her life."

They heard earlier from consultant forensic psychiatrist Dr David Ho, who told them Levy had been diagnosed with severe depression and emotionally unstable personality disorder (EUPD).

He argued that the EUPD combined with his depression meant he was not thinking rationally at the time of the incident and rendered him incapable of premeditating the killing.

Dr Ho said: "If not for the two mental disorders, I do not believe that Mr Levy would behave in the way he did.

"He was not so unwell that he completely lost control so he was completely unaware of what he was doing. However, it was diminished."

He added the confession was Levy’s way of "making sense" of the brutal incident in which Ms Stevens’ body was found in the hallway of Levy’s flat.

"I think his speech has to be seen within the whole context, especially with regards to saying he wished to kill Ms Stevens, it needs to be seen in the context of his disorder," Dr Ho said.

"He was not psychotic, or to use the lay term, 'mad'. He was trying to understand what was going on around him, however it was his interpretation of this, that was wrong."

Jurors were told Levy had previously attempted suicide in 2016 following the breakdown of a relationship, demonstrating a significant fear of abandonment, one of the symptoms of EUPD.

"On that occasion he turned his anger on himself and on this occasion he turned it on someone else," Dr Ho said.

Levy, of Great North Way, Hendon, pleaded not guilty to murder on the grounds of diminished responsibility.

The trial continues.