Blasting heads 'will change Melbourne Bay'

The Victorian opposition believes Melbourne's beaches will be irrevocably changed if the Port Phillip Bay Heads are blasted to allow bigger container ships through.

The government refused to say whether it would ban the potential new owners of the port of Melbourne from opening up the heads to allow larger ships into the bay.

"It is inevitable that a private operator seeking to bring bigger ships into Victoria will seek to blast the heads and blasting the heads will completely change Port Phillip Bay. It will change the beaches," opposition leader Matthew Guy said on Friday.