Footage has emerged showing a French tanker steaming into a breakwater at the port of Marseille.

The incident involving the 3,500-dwt Cap Pinede (built 2009) occurred over the weekend at the northern entrance to the Mediterranean terminal, French media reported.

A video shows the vessel approaching the breakwater, as one onlooker asks, "Why doesn't he just stop?" Another says, "I don't know. He cannot stop."

As the tanker gets to within a few metres of the breakwater, the observers say "Boom" and the tanker then hits with an audible metallic clang, rising up a little against the structure, before it reverses off and away.

"Mama mia," one onlooker says.

No details have been given about damage to the vessel. No injuries or pollution were reported.

French manager Compagnie Fluviale de Transport (CFT) has been contacted for further information.

La Provence reported that the tanker was able to return to a berth where it remained on Tuesday.

A firefighting boat is in attendance as a precaution.

The tanker has insurance through Shipowners' Mutual. It has no listed port-state control inspections.