A man has been found guilty of sexually assaulting a woman who spurned his advances because she was dancing with her husband.

The couple were dancing when Steven Green, 22, butted in between them.

He initially put his arms around both of them but then turned his back on the man after being told they were a married couple.

Even though he was warned off, Green persisted in grabbing hold of the woman and shoving his hand under her clothing before groping her.

Green, who was drunk, claimed in court he was just being friendly and denied indecently assaulting the woman but a sheriff found him guilty and placed him on the sex offenders register.

Perth Sheriff Court was shown footage of the incident which took place in the Loft nightclub in Perth during a Halloween party in the early hours of November 1 last year.

Green could clearly be seen grabbing hold of the woman and, with his back to her husband, lurching forward several times to try and kiss her.

Green, of Kingswell Terrace, Perth, was found guilty of behaving in a sexualised manner and grabbing hold of the woman's body, placing his hand under her clothes, touching her genitals and repeatedly trying to kiss her.

The woman, from Perth, was visibly distressed as the CCTV footage from the club was shown in court and she said she had been shocked by his behaviour.

She told the court she had been at an organised fancy dress party and she and her doctor husband, who were recently married, had gone as fairy tale characters.

The woman, who cannot be named for legal reasons, said they had been dancing together when Green came staggering over to join them.

She said she told him she was with her husband but he refused to go away and instead continued trying to kiss and grope her until he was finally taken away by stewards.

Fiscal depute Rebecca Kynaston told the court: "Initially she was OK with his attention but he then crossed the line. She was unhappy with the way he was touching her and attempting to kiss her.

"She did not encourage him in any way and it was not welcome attention. There was certainly no evidence of consent.

"The CCTV footage is quite explicit in showing the sexual element. She was there with her husband, dancing with her husband. She wasn't putting herself out there as a single person. There was a significant sexual element to this charge."

Sheriff Christopher Shead said: "The court did not accept his denial. It did not regard that evidence as in any way credible."

Sentence on Green was deferred for the preparation of reports.