A PERTH man has been fined $400 for using his mobile phone while driving – incredibly telling police he was watching pornography on the device.

The incident happened on Abernethy Road in Belmont.

The man was driving a Mitsubishi Triton when he was pulled over for the offence.

Camera Icon Image Credit: Supplied / Greig Johnston

When asked why he was using the phone, the man told officers: “I was watching porn.”

As well as the $400 fine, he has been docked three demerit points.

The WA Police Traffic Twitter account posted a section of the man’s infringement notice last night.