NSW man stole and spat in cop's face

A man has allegedly robbed two people with a pocket knife before spitting into the face of a NSW police officer.

The 47-year-old asked two workers at a building site in West Tamworth for cigarettes and money and threatened them the knife when they refused.

He then stole a mobile phone from one of the men and spat in the face of one of the officers who arrested him while being escorted to a paddy wagon.

The man has been refused bail while the officer was taken to the local hospital for treatment.