A 23-year-old man, charged with assaulting a police officer who was knocked unconscious near Turangi yesterday, was granted interim name suppression when he appeared in Taupo District Court this afternoon.

The Auckland man, who was wearing a police boiler suit in court, was remanded by Justice of the Peace Doreen Blyth to appear again on April 20.

The 59-year-old officer, the sole officer on highway patrol duty, was breath testing a suspected drink driver on State Highway 1 near Turangi, south of Lake Taupo, about 3.30am.

The driver allegedly failed the test and the officer was punched without warning, and knocked unconscious, Inspector Ben Offner, of police northern communications, said yesterday.

The officer suffered concussion and serious facial cuts in the attack. He was taken to Taupo Hospital, where he received a number of stitches before being discharged.