If China recognises India's sovereignty over Sikkim it may gain more access to the expanding Indian market, Srikanth Kondapalli, China scholar and research fellow at the Institute of Defence Studies and Analyses, told rediff.com.

Media reports have suggested that intense efforts are underway to resolve Sino-Indian differences on the Sikkim issue before Prime Minister Atal Bihari Vajpayee's scheduled visit to China next month. 

Sikkim became part of the Indian Union in 1975. China had then taken 'strong' objection to the merger, terming it as 'illegal occupation by India.' The Chinese position, Kondapalli said, was in sharp contrast to India's recognition of Tibet as an integral part of China.

In fact till the 1990s China had been vocal in its opposition to the merger of Sikkim. The decibel levels of Chinese protests reduced after a détente between the two countries in 1995-96, when then Indian Prime Minister P V Narasimha Rao signed an agreement with his counterpart Li Peng in New Delhi.

Foreign Minister Jaswant Singh's March 2002 visit to Beijing, while further softening China's stand on Sikkim, did not, as the Indians wanted, culminate in Beijing fully acknowledging Indian sovereignty over the northeastern state.

The tactical Chinese move to grant India political legitimacy over Sikkim has been necessitated because China wants to improve its management of Tibet and want to increase trade across Indo-China border. By recognizing Sikkim China wants some leverage on the pending border dispute with India and trade-related issues.

"Sino-Indian border trade is valued at over $100 million. This trade can be facilitated if the route through Sikkim is opened up," Kondapalli said. "Sikkim is the lifeline of Tibet. For the better management of Tibet China needs to regularise food supplies through Sikkim."

Moreover, any border trade between Sikkim and China, millions of dollars according to some estimates, can be extended till Kalimpong in West Bengal and further to Bangladesh. 

Many years ago Yatung in Tibet had a flourishing trade with Sikkim and China's aim, Kondapalli said, is to revive it.

If the Sikkim route is opened up, China could think of using the Siliguri corridor to reach Bangladesh.

The 180-km long corridor is also the lifeline of the Indian Railways and Indian military. Any opening up of this region, he said, will have to take into account security considerations.

China has also started constructing railway lines from Tibet to the Indian border. By 2007, the lines are expected to be operational.

The construction of such an ambitious railway network, when seen in the context of China's recent defence pact with Bangladesh, throws light on the Chinese plan of setting up a supply corridor stretching from Bangladesh, West Bengal, Sikkim and all the way into Tibet.