The best friend of a woman who was stabbed to death by her estranged husband told a jury yesterday how he berated his wife telling her she was fat and useless in bed.

Nicola Bastable, who had been friends with victim Sarah Smart for more than 10 years, told Oxford Crown Court how Brian Smart who stands accused of murdering his 27-year-old wife "put down his wife an awful lot", criticising her looks, their sex life, the untidiness of the family home and the way she cared for the children.

Smart admits the manslaughter of his estranged wife but denies murdering her and claims diminished responsibility.

Ms Bastable told the court how she had received a telephone call from Mrs Smart at about 6.30pm on January 5, the night of the alleged murder.

She said: "She told me Brian was there and they were talking. He wanted to know where she had been on the night of December 8, 2004, when we had been out with colleagues for a group meal. She handed the phone over to me to tell Brian that that was the truth.

"I spoke to him and told him we had been at a meal that night. He just said: 'Yeah, right, whatever'."

On December 8, 2004, less than a month before Mrs Smart was allegedly murdered by her 40-year-old husband, the jury heard how the couple had a row after Mrs Smart found a condom in a bedroom drawer.

Ms Bastable said: "As Brian had had a vasectomy, Sarah thought that he might be having an affair. She said this was the final straw and was thinking of throwing him out. This marked a split in the marriage. She felt she could no longer trust him."

She then went out with friends for the evening, including Ms Bastable.

Two days later, she told him to leave the family home, in Barton Village Road, Barton, Oxford, where the stabbing took place.

About a week later, Ms Bastable told the court how Smart appeared at her door, crying.

She said: "He told me he had lost everything his marriage and his kids.

"He seemed upset, he sounded like he was crying, but there were no tears. I sensed it was a bit of an act.

"He then asked me if I would like to start courting him, which made me feel very uneasy."

The court also heard from Mrs Smart's half sister, Melanie Leggett, who said her sibling had been unsure whether to marry Smart, but reached a point where arrangements had been made for the wedding, so she went ahead with it. The relationship deteriorated soon after they were married, in September 2003, with Mrs Smart having to give up her midwifery course because Smart grew tired of being a househusband.

The case continues.