The conflict between India and Pakistan over Kashmir offers a potentially rich intelligence harvest for China in its own rivalry with India as it gleans data from its fighter jets and other weapons used in action by Pakistan.

Security analysts and diplomats say China's military modernisation has reached a point where it has the ability to deeply scrutinise Indian actions in real time from its border installations and Indian Ocean fleets as well as from space.

"From an intelligence perspective, this is a rare target of opportunity right on China's borders involving a key potential adversary," said Singapore-based security analyst Alexander Neill.

Security analysts say both sides have taken steps to strengthen their military facilities and capabilities along the border, but it is also from above that China packs an intelligence gathering punch.

The London-based International Institute for Strategic Studies (IISS) notes that China now fields 267 satellites - including 115 devoted to intelligence, surveillance and reconnaissance and a further 81 that monitor military electronic and signals information. It is a network that dwarfs its regional rivals, including India, and is second only to the US.

"Both in terms of space and missile tracking capabilities, China is much better off now in terms of being able to monitor things as they happen," said Neill, who is an adjunct fellow at Hawaii's Pacific Forum think-tank.

China's defence ministry did not immediately respond to Reuters' questions about the deployment of its military satellites and other questions about its intelligence gathering.

Pakistan's military media wing and information minister did not immediately respond to a request for comment on any information sharing with China. Pakistan has previously said it has an "all-weather strategic, cooperative partnership" with China.

India has not commented on the issue, but its top diplomat in Britain, High Commissioner Vikram Doraiswami, told Sky News on Thursday that China's relationship with Pakistan was not a concern for India.

"China requires a relationship with all of its neighbours, that includes us," he said.

Chinese military intelligence teams would be eager to garner information on any Indian use of air defences and launches of cruise and ballistic missiles - not just in terms of flight paths and accuracy but command and control information, analysts and diplomats say.

Any deployment of India's BrahMos supersonic cruise missile - a weapon it developed jointly with Russia - would be of particular interest, some analysts say, given they do not believe it has been used in combat.

China has also beefed up its intelligence gathering at sea. It has been increasingly active in the Indian Ocean in recent years, with China deploying space tracking ships as well as oceanographic research and fishing vessels on extended deployments, open source intelligence trackers say.