The 30-year-old victim, who has not been named, sustained bruising to his face and a swollen lip as a result of the attack. He did not require hospital treatment, but was left extremely shaken.

A police spokesperson said, “The man was returning home from celebrations with family at around 2.30 am when he was approached by two males riding BMX bikes.

“They engaged him in conversation before one head-butted him, causing him to fall to the ground.

“The pair then made off with his Nokia mobile phone and a small sum of money.”

One of the culprits is described as being around 17 years old, between 5ft 8in and 5ft 10in tall, with long fair hair. He was wearing a white hooded top, dark bottoms and white trainers.

The other is thought to be about 15 years old, around 5ft 5in tall and was also wearing a white hooded top and dark bottoms.

Police have also issued an appeal for information about an assault in Dundee, which left a 24-year-old man hospitalised with a collapsed lung.

The victim was taken to Ninewells after he was found at around 3.45am on Boxing Day within a garden in Westcroft Road, Mid Craigie.

He is believed to have been the victim of an assault in the area of Drumgeith playing fields shortly before he was found.

Anyone with information about either incident is asked to contact the police on Dundee 223200 or speak to any officer.