Following a spate of large-scale oil spills the Australian government has blamed its nations worst offshore oil leak on PTTEP Australasia, a unit of Thailand's PTT Exploration and Production.
Since August 2009 more than 400 barrels of oil a day spewed from the West Atlas rig and Montara wellhead platform north of Australia into the Timor Sea off Australia's north coast for 10 weeks.
It was plugged on a fifth attempt in November 2009, after a slick had spread an estimated 90,000 sq km (35,000 sq miles).
The Australian Resources Minister told parliament the Thai firm should have its operating licence reviewed.
The company paid AU$390 million (286 million) for the clean-up but the minister said he thought relevant laws needed to be strengthened to make absolutely clear that companies would be held responsible for any future leaks.
The minister also criticised the Australian government regulator which had pursued a minimalist approach in handling the emergency, saying the entire incident had been avoidable.
The government ordered the inquiry while environmentalists have expressed concerns about the waters off Australia's north-west coast, which are home to whales and dolphins.