Police have warned drivers not to swerve for wildlife after a fatal collision on the Princes Highway at Pomborneit on Wednesday evening.

Colac police highway patrol unit Senior Constable Annie Cauchi said the driver of a Kia Rio sedan was believed to have swerved to miss a koala before the collision.

The 31-year-old Colac man was heading west on the Princes Highway before being involved in a collision with a 50-year-old Melbourne man, driving a truck carrying a large water container.

"The driver of the Kia Rio is believed to have swerved to miss a koala, then skidded backwards into the path of the truck," she said.

"The front of the truck impacted the rear of the Kia Rio in the east bound lane."

Senior Constable Cauchi said drivers needed to be aware of wildlife.

"We are requesting that all drivers take all possible care and remain vigilant," she said.

At 10.53am Thursday:

Police have confirmed a man in his 30s died in a fatal collision at Pomborneit on Wednesday evening.

A police spokeswoman said the man was not from the Camperdown district.

She said the driver of the car and the truck were travelling in opposite directions on the Princes Highway when collision happened about 6.20pm.

The driver of the truck, who was not injured, is also not a local resident.

Colac police highway patrol unit officers are in charge of the ongoing investigation.

At 6.45pm Wednesday: The male driver of a car has died in a fatal crash on the Princes Highway at Pomborneit on Wednesday.

A police media spokesperson said investigators had been told a car and a truck collided on the highway near the Koallah-Pomborneit Road about 6.20pm.

The yet-to-be-identified male driver of the car died at the scene, the police spokesperson said.

The male driver of the truck was not injured.

Police are now investigating the circumstances surrounding the fatal collision.

Victoria's road toll now stands at 120 compared to 90 at the same time last year.

Anyone who witnessed the collision or with dashcam footage is asked to contact Crime Stoppers on 1800 333 000 or visit www.crimestoppersvic.com.au

Earlier: Emergency services have been called to an accident on the Princes Highway at Pomborneit on Wednesday.

An Ambulance Victoria spokesperson said they were called to the scene about 6.20pm.

The spokesperson said one person was being assessed, but there were no further details available.

At least six emergency services vehicles were called to the scene.

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