"Arunachal Pradesh has always been, and will always be an integral part of India. Assigning invented names to places in Arunachal Pradesh does not alter this fact," Bagchi said.

Asked for his reaction to India's assertion, Chinese Foreign Ministry spokesman Zhao Lijian told a media briefing here that "Zangnan (the southern part of China's Tibet) is located in the Tibet Autonomous Region of China.

"It has been China's territory since the ancient times," he said in updated comments posted on the Chinese Foreign Ministry website.

China refers Arunachal Pradesh as Zangnan.

Earlier, Zhao said "the southern part of Tibet belongs to the Tibetan Autonomous Region of China and it has been China's inherent territories".

"China's ethnic minorities such as the Moinba and Tibetan ethnic groups have lived and worked in this area for a long time, and many place names have been passed down," he said.

"In order to strengthen the standardised administration of place names, the competent department of the Chinese government, in accordance with the regulation on the administration of geographical names, has announced the second batch of standardised names of places in Zangnan for use by the public, which completely falls within China's sovereignty," Zhao said in the updated comments.

This is the second batch of standardised Chinese names of places in Arunachal Pradesh released by China.

The first batch of the standardised names of six places was released in 2017.

China claims Arunachal Pradesh as South Tibet which is firmly rejected by the External Affairs Ministry which has asserted that the state is an "inseparable part of India".

Beijing routinely protests visits of top Indian leaders and officials to Arunachal Pradesh to reaffirm its claim.

The India-China border dispute covers the 3,488 km long Line of Actual Control (LAC).

China's renaming of the places in Arunachal Pradesh came in the midst of the lingering eastern Ladakh border standoff that began in May last year.