A man has been charged after he allegedly failed to wear a face mask on public transport and bit a police officer on the stomach in NSW.

Police say the 43-year-old man was seen without a mask while travelling on a southbound train between Gosford and Woy Woy just after 3pm on Saturday.

When officers questioned whether he had a mask and asked for identification, he allegedly refused and became aggressive.

“As police attempted to arrest him, he tried to punch officers before OC spray was deployed,” police said in a statement on Sunday.

The man allegedly punched a constable before he was wrestled to the ground and bit the constable twice on his stomach and finger, causing cuts and bruises.

The man allegedly punched and kicked police officers, and bit one of them. Picture: NCA Newswire/Gaye GerardSource:News Corp Australia

After he was removed from the train, the man allegedly became violent again on the platform and kicked out at officers.

The constable was taken to Gosford Hospital for treatment and was later released.

The accused man has been charged with not wearing a fitted face covering on public transport, failing to comply with a direction, resisting an officer in the execution of their duty, and assaulting a police officer causing bodily harm.

He has been granted conditional bail and is scheduled to face Woy Woy Local Court on February 11.