Australian officials say the damage to the Great Barrier Reef caused by a Chinese freighter that ran aground is worse than first thought. The vessel has been re-floated and now is safely anchored off the Queensland coast.

The Great Barrier Reef Marine Park Authority says damage to the reef is so severe it could take marine life 20 years to recover.

After it ran aground, the Shen Neng 1 was dragged over the reef by ocean currents, crushing coral and plants, and smearing them with potentially toxic paint.

The Chinese coal carrier struck a sandbank off Queensland more than a week ago. After the boat leaked about three tons of oil into the pristine waters, salvage workers managed to unload 950 tons that were in the fuel tanks. Then the boat was re-floated and taken to a safe anchorage.

The government is preparing tough new measures to regulate foreign ships using Australian waters and ports.

"We are quite prepared to take whatever measures are required," said Transport Minister Anthony Albanese. "The cost will not be a consideration at all because the cost of damage to our reef [is] incalculable not just in economic terms but on environmental terms for future generations." .

On Monday, three crewmen from another foreign vessel that allegedly entered restricted waters in the Great Barrier Reef appeared before magistrates in Queensland. They are charged with entering a prohibited zone without permission.

The South Korean master and two Vietnamese officers of the Panama-flagged coal boat MV Mimosa were granted bail and ordered to reappear in court later this week. They face fines of up to $205,000.

The Great Barrier Reef is the world's largest coral system. It stretches for 2,300 kilometers along Australia's northeast coast and is home to a vast array of wildlife. It is prime tourism destination that draws tens of thousands of people a year. However, it faces damage not just from shipping, but also from fresh water run-off from Australian coastal farm land and rising sea temperatures.