A man attacked and threatened to kill his pregnant girlfriend after accusing her of sleeping with his friends.

Dale Duncan targeted the 19-year-old after a night of heavy drinking with friends by punching and kicking her, and throwing her around by the hair.

After the assault the 24-year-old told his victim: "I'm away to get back on it."

At Dundee Sheriff Court on Thursday, Duncan admitted attacking the teenager in the early hours of August 2.

Duncan turned up at his then-girlfriend's home in Dundee at around 5am and began accusing her of sleeping with his friends before grabbing her by the hair and punching her full force in the face.

After punching her he began kicking and jumping on her with both feet.

He then grabbed her by the throat he told her: "That's it, I am away to f*****g kill you."

The victim suffered bruising and swelling to her eye, lumps on the back of her head and cuts and bruises to her legs and arms.

At the time of the incident the couple had been in an on-off relationship for two years and the victim was pregnant with their first child.

Duncan was not aware of the pregnancy at the time of the attack.

Ms Robertson said: "They had been in an on off relationship for two years. She was pregnant with her first child, albeit neither she nor the accused knew about the pregnancy at the time.

Duncan, a prisoner at HMP Perth, has been remanded in custody with sentencing deferred until January.