"This earthquake has the potential to generate a widely destructive tsunami in the ocean or seas near the earthquake. Authorities in those regions should be aware of this possibility and take immediate action. This action should include evacuation of coasts within a 1000 km of the epicentre," the warning said.

The quake, that took place about four hundred kilometres south east of Banda Aceh, have been upgraded to a magnitude of 8.7 on the richter scale by the US Geological Survey from an initial reading of 8.2.

Indonesia

The Indonesian Information Minister (Sofyan Djalil) says so far his government has not received reports of a tsunami developing, but they were watching the situation closely.

A BBC correspondent in the Indonesian province of Aceh says people living in coastal areas have begun moving to higher ground.

A BBC correspondent in Singapore says first reports from the Indonesian province of Aceh say many people in low-lying regions have left their homes.

India

India has told residents of its Andaman and Nicobar islands to move to higher ground.

The French news agency says a hotel owner there has told them that he felt a massive jolt, and people still recovering from last December's tsunami were fleeing in panic.

Malaysia

A BBC correspondent in the Malaysian capital, Kuala Lumpur, says the earthquake could be clearly felt in the city and caused many people to leave their buildings.

The earthquake struck an area off the western coast of the island of Sumatra, south of the point where last December's tsunami orginated.

A spokesman for the US Geological Survey (Dale Grant) said it was the largest earthquake in the Indian Ocean since then.