Oil giant TotalFina, which chartered the ill-fated oil tanker Erika, tightened its policy on chartering older tankers. However, company officials stressed that a new age limit on large ships, which would not have stopped it chartering the mid-sized Erika, needed to be backed up by tougher international maritime standards and greater transparency of safety checks.
"We still need a global initiative and we are still calling for tighter controls and for charterers to have more access to documents (on seaworthiness checks)," TotalFina spokeswoman Isabelle Galldraud said
The company is cutting to 20 years from 25 the upper age limit on chartered vessels of 80,000 deadweight tons and above, while keeping it at 25 years for smaller ships.
The Maltese-registered Erika, of 37,283 tons dwt, was 25 years old when it split apart and sank off the French coast last month, spilling thousands of tons of fuel oil that polluted a 400 km (250 mile) swathe of the French coast.
A preliminary report by the French Transport Ministry said a corroded bulkhead was probably the main cause of its sinking.
Galldraud said it was impossible to extend the 20-year age limit to smaller vessels as there were not enough young ships on the market in that category.
"It's a simple supply problem," she said. "We are taking immediate measures but we can only do what is realistic."
Thierry Desmarest, said the spill was now pegged at around 15,000 tons, bigger than an initial estimate of 10,000 tons.
That would mean some 15,000 tons of oil is still trapped in the hold of the sunken wreck.
Some 100,000 tons of sand, seaweed and other matter glued together by the sticky, black fuel oil has so far been scraped off beaches by volunteers and army troops.
The accident has sparked widespread calls for tougher international shipping standards and French President Jacques Chirac has vowed to push for global laws forcing polluters to pay for more of the damage caused by oil slicks.
Desmarest, who has said his firm has no way of independently inspecting the ships it charters, urged the creation of a pan-European maritime safety board which would take the responsibility for seaworthiness off shipowners and charterers.
A group of 41 oil majors have said they will start making tanker inspection reports available to port examiners in Europe.