Gurkha soldiers of the Indian Army walk on Siachen glacier, India, in 2000. Siachen glacier is the highest battlefield in the world. (Associated Press/Ajit Kumar) Indian Kashmir's glaciers are melting fast because of rising temperatures, threatening the water supply of millions of people in the Himalayan region, a new study by Indian scientists says.

The study by Kashmir University's geology and geophysics department blamed the effect on climate change, and said it endangers the livelihoods of two-thirds of the region's nearly 10 million people engaged in agriculture, horticulture, livestock rearing and forestry.

The Kolahoi glacier, the biggest in the Indian portion of divided Kashmir, has shrunk to about 11.5 square kilometres from about 13 square kilometres in the past 40 years, the study found.

Shakil Romshoo, an associate professor in the department who led the three-year study, described the rate of melting as "alarming." He said Tuesday that Kolahoi had shrunk by 18 per cent, and over the same period, other glaciers in the region had shrunk by 16 per cent.

The Kolahoi feeds Kashmir's lifeline Jhelum River, which is also vital for agriculture in Pakistan's most populous province of Punjab.

The study was released Monday at a workshop on the impact of shrinking glaciers held in Srinagar, the capital of Indian Kashmir.

Last year, international charity ActionAid also warned that the glaciers in most areas of Kashmir have shrunk. The group said that climate change was affecting rain and snowfall patterns, which was lowering food production.

Prof. Syeed Iqbal Hasnain, head glaciologist at New Delhi-based the Energy and Resources Institute, said the findings show again that "warming of the climate system was unequivocal."

Rajeev Upadhay, an Indian geologist who has studied glaciers since 1995, said the new study was in line with previous ones.

"The study confirms the general trend that about 90 per cent of all Himalayan glaciers are receding. Some glaciers are receding at an alarming rate of 44-45 metres per year," said Upadhay, who was not involved in the Kashmir University study.

He also said the Siachen glacier, where rival Indian and Pakistani troops have been entrenched for 25 years, has melted to half its earlier size.

"The unusual climate change clubbed with other activities at the Siachen Glacier has reduced it to 74 kilometres from 150 kilometres in length," he said.

The Siachen Glacier is often dubbed the world's highest battlefield. The nuclear-armed South Asian nations have competing territorial claims to Siachen and troops have been locked in a standoff there at an altitude of up to 6,100 metres since 1984.

India and Pakistan have fought two wars over control of Kashmir since 1947 after they won independence from Britain. Both claim the divided territory in its entirety.