The Transport Minister has warned people to be cautious with the Sydney CBD light rail testing now underway.

Construction began more than three years ago and was expected to open 14 months ago.

A series of issues pushed that date back and the light rail is now set to open in May 2020.

But Transport Minister Andrew Constance tells Ben Fordham they are hoping to have it completed by Christmas.

Mr Constance says people need to be more aware of the trams as they begin daytime testing.

“People will start to see the trams moving in and around the city and they will need to be tram aware.

“These are much quieter vehicles than the vehicles that Melbourne runs on their tram track so they can creep up on you.”

Click PLAY to hear the full interview