A woman will face court on Tuesday charged with allegedly threatening an employee with a knife at a service station in Newcastle. 

About 6.15pm on Monday night a 39-year-old female attendant was working at a service station on Park Avenue, Kotara, when a 37-year-old woman entered the store and approached the counter.

Police allege the woman then threatened the employee with a knife and demanded cigarettes.

The employee refused and the woman left the store.

Officers attended a short time later and arrested the woman.

She was taken to Newcastle Police Station and charged with robbery armed with an offensive weapon.

She was refused bail to appear at Newcastle Local Court on Tuesday.