A man armed with a knife has threatened a taxi driver and made off with his takings in a frightening robbery overnight.

The driver was parked on the side of the road in Bentleigh East when a man approached the car just after 3am.

The victim, a 63-year-old Bentleigh East man, told police he was sitting in his car and the unknown man spoke to him through the driver’s side window.

The man threatened the driver with knife and demanded that he hand over his takings.

The victim handed over an amount of cash and the man ran off along Centre Road.

The man is described as being approximately 175cm tall and wearing dark clothing.