Melbourne’s morning commuters were greeted by traffic gridlock after a multi-car pile-up during peak hour.

The multi-vehicle crash initially closed all outbound lanes of the Western Fwy between the M80 Ring Rd and Robinsons Rd near Derrimut, early on Friday morning.

Motorists were advised to use Boundary Rd through Laverton North or Ballarat Rd through Deer Park.

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While city-bound lanes remained open, commuters were warned to expect significant delays.

“The closure is under the control of Victoria Police. All lanes will reopen as soon as it is safe to do so,” an alert from the Department of Transport said earlier.

“Our signals team is monitoring conditions in the area and will adjust traffic lights to minimise congestion along detour routes.”

All lanes have since reopened but traffic remains heavy in the area.