Mandatory one-punch sentence in NSW

NSW Premier Barry O'Farrell says his government will introduce an eight-year mandatory minimum sentence for one-punch offences committed under the influence of drugs or alcohol.

"We are sending a clear message about alcohol and drug-induced violence," the premier told reporters in Sydney on Tuesday.

He said parliament would be recalled early to pass a suite of new measures including a one-punch law that would have a 20-year maximum, rising to a 25-year-maximum where drugs and alcohol are involved.

Additionally, maximum penalties for serious assaults involving drugs and alcohol will increase by two years and mandatory minimums will also apply.

Mr O'Farrell said 1.30am lock-outs would be introduced at licensed premises across an expanded Sydney CBD precinct and there would be an end to drinks at 3am.

"This is about trying to send a very clear message to the industry that yes, you can continue to trade after 3 o'clock, but drinks will cease at 3 o'clock."

The premier said there would also be a new statewide closing time of 10pm for bottle shops.

"Licensed venues alone are not the source of all the alcohol problems across NSW, bottle shops have to play their role as well."