NEW DELHI, Aug 4 (Reuter) - India and China started two days of talks on Monday towards resolving a longstanding border dispute which led to a brief war in 1962, officials said.

Senior officials from the neighbouring giants' foreign ministries began the 10th meeting of a joint working group set up in 1988 during a visit to Beijing by then Indian prime minister Rajiv Gandhi.

Indian Foreign Secretary K. Raghunath and Chinese Vice Foreign Minister Tang Jiaxuan led the delegations, Indian officials said.

The Press Trust of India said the two sides reviewed military confidence-building measures along the line of control separating the two countries, which share a 4,500-km (2,800-mile) border and between them have one third of the world's population.

During a visit to New Delhi last November by Chinese President Jiang Zemin, the two nations agreed to reduce troops and armaments along their Himalayan boundary.

The pact fleshed out an agreement in principle signed by former prime minister P.V. Narasimha Rao in Beijing in 1993.

China claims large parts of Arunachal Pradesh and Sikkim, both states in northeastern India. Chinese officials have in the past said Beijing was ready to concede the annexation of Sikkim to India, but no agreement has been reached.

Sikkim is strategically vital to India as it borders Tibet. It was annexed by New Delhi in 1975 after its legislature voted to abolish the monarchy and join the Indian union.

China claims some 90,000 sq km (35,000 sq miles) of Arunachal Pradesh. New Delhi says Beijing occupies about 33,000 sq km (13,000 sq miles) of the Aksai Chin region which it says is part of India's Jammu and Kashmir state.