A Bhutanese army official told AFP by telephone that the operations, launched on December 15, had "almost reached the last leg with our troops destroying all the 30 militant camps".

"Quite a large number of rebels are still inside the jungles of Bhutan, although we are zeroing in on them," he said.

A Bhutanese government spokesman said the kingdom hoped the rebels would surrender and avoid further bloodshed.

"There cannot be a better gift on this New Year's Day than offering to withdraw the military operations against the anti-India militants if they agree to leave the kingdom peacefully," the spokesman said.

Bhutan launched its first modern military operation after the rebels defied six years of threats to leave the kingdom, from which they had launched attacks in the troubled Indian state of Assam.

The Indian army, which helps train the Bhutanese army, says more than 140 rebels have died along with eight Bhutanese troops and support personnel since the offensive started.

Bhutan has not released casualty figures but says some 500 rebels had surrendered. Indian officials say at least 100 rebels are in their custody.

The rebels deny any major losses.