It recommended evacuating all civil servants and migrants originally from other parts of Indonesia, and putting army units in the evacuation areas on combat alert.

The assessment predicts economic collapse and talks of preparing the western half of Timor island for an influx of refugees.

"Evacuation routes must be planned and secured," it said.

The UN mission in East Timor said it was studying the report, which it received from a government source.

But an Indonesian Foreign Ministry spokesman in Jakarta denied its authenticity.

UN concerns

Two days of talks to discuss the role of the United Nations in East Timor immediately after next month's referendum have been held in New York.

The talks - hosted by the United Nations special envoy, Jamsheed Marker - involved senior officials from Indonesia and the former colonial power, Portugal.

Afterwards Mr Marker said it was clear that some form of increased security would be needed to ensure that violence did not escalate in the aftermath of the ballot.

The territory's 800,000 people will vote on 21 or 22 August to decide whether to move towards complete independence, or opt for autonomy within Indonesia.

Intimidation

Voter registration has begun

Meanwhile, a UN spokesman in the Timorese capital, Dili expressed concern on Monday that anti-independence militias are still intimidating workers registering voters for the referendum.

A registration centre in the town of Cassa was closed after members of an anti-independence militia harassed its staff, said UN spokesman David Wimhurst.

He said: "Every bit of intimidation works against the consultation process and that is a concern."

Anniversary

On Sunday, more than 3,000 people including many unarmed militia attended a rally to celebrate Indonesia's annexation of the province.

The commander-in-chief of the pro-Jakarta militias, Joao Tavares, was at the pro-integration celebration in Balibo, near East Timor's western border.

In 1975, about a dozen leaders signed a declaration in the town inviting neighbouring Indonesia to take formal control of the former Portuguese colony.

Indonesia considered the declaration as an invitation and used it as justification for its annexation of East Timor, which took effect a year later.

Mr Tavares told supporters that East Timor did not need to achieve independence because, within Indonesia, it was already part of an independent nation.

"We have been Indonesians together with 200 million other Indonesians for more than 20 years. This year's celebration will not be the last," he said.

United Nations military liaison officers observed the ceremony.