In ancient times, India and China had close trade and cultural relations. India was one of the first countries to recognise the People’s Republic of China, which was formed in 1949.
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Later on, India also supported that country’s admission into the UN.
In 1954, India and China entered into a treaty of friendship based on five principles, called the Panchsheel (panch means five and sheel means a way of conducting oneself). By this treaty, India also formally recognised China’s authority over the Himalayan territory of Tibet situated between India and China.
However, tensions arose over the definition of the India-Tibet border. China claimed vast areas in the Indian territories of Ladakh and Arunachal Pradesh (earlier North-East Frontier Agency, or NEFA).