Prime Minister Manmohan Singh Friday took off on his fourth visit to Jammu and Kashmir, during which he will acquaint himself with the situation on the Siachen glacier, the world's highest battlefield.

In addition to laying the foundation stones of two power projects at Kargil and Leh Saturday during the three-day trip, he will make an aerial survey of the Siachen region and interact with some of the troops deployed there Sunday.

He will be the first prime minister to visit Siachen, the scene of a standoff between Indian and Pakistani forces since 1984.

Manmohan Singh is also expected to address a small public gathering at Leh, the headquarters of the Ladakh region, Saturday and inaugurate the annual Sindhu Darshan tourism festival Sunday after returning from Siachen.

Officials said the prime minister's trip to Siachen was part of his efforts to acquaint himself with the ground situation on the glacier as India and Pakistan continue with efforts to demilitarise the region.

The visit is aimed at boosting the morale of troops deployed on Siachen at heights of up to 21,000 feet, the officials said.

The prime minister has been declared fit by doctors to undertake the visit but will spend a day at Leh Friday to acclimatise himself.

Manmohan Singh is being accompanied to Siachen by the Indian Army chief, Gen. J.J. Singh, who recently made a trip to the region to supervise arrangements for the prime minister's trip.

Guns on the glacier have been silent since India and Pakistan agreed to a ceasefire along the frontiers in Jammu and Kashmir in November 2003, but adverse weather conditions there continue to claim lives on both sides.