A man has been arrested after allegedly glassing another patron at a hotel in Lake Macquarie yesterday evening.

About 10pm (Friday 1 April 2016), officers attached to Lake Macquarie Local Area Command were called to a licensed premises on John Street, Warners Bay, following reports of an assault.

Police arrived to find a 24-year-old Belmont South man had sustained serious lacerations to his neck after allegedly being struck with a glass.

Investigators have been told the injured man had been involved in a verbal dispute with another patron earlier in the evening.

The situation escalated with the other man, aged 19, allegedly striking the older man in the neck with a glass.

The older man was treated at the scene by NSW Ambulance Paramedics, before being taken to John Hunter Hospital in a serious condition.

He remains in hospital and is now believed to be stable.

The younger man was taken to Belmont Hospital under police guard for treatment to minor finger lacerations.

A crime scene was established at the hotel, which was examined by detectives and specialist forensic officers.

Investigations into the matter are continuing and charges are expected to be laid.