Trucking magnate Lindsay Fox’s claim on extending his Victorian beachfront property may be short-lived.

The state’s land titles office extended Mr Fox’s Portsea property boundary to include an extra 45 metres of prime beach land, reportedly worth an estimated $5 million.

The decision, made on Christmas Eve, involved a new legal interpretation of the high water mark on an old land title.

But Premier Denis Napthine says the government is looking at passing new laws to clarify such land title boundaries to prevent a flood of similar beach land grabs.

“Beaches fundamentally should be for the public,” Dr Napthine told reporters on Monday.

“We will be examining the total issue of how titles operate, and some of these old titles being perhaps put into a more modern format that provides greater certainty and security.”

Planning Minister Matthew Guy said the new laws will likely look at defining the high-water mark at the time of purchase, or by a certain date.