The Asian giants have been warming ties since a deadly 2020 border clash, with flights, visas and high-level contacts gradually being restored.

"At the invitation of Prime Minister of the Republic of India Narendra Modi, President Xi Jinping will attend the 18th BRICS Summit in New Delhi from September 12 to 13," a foreign ministry statement read.

Modi visited China in August last year, in a first sign of the cautious thaw.

However, deep mistrust remains, with their contested frontier, a widening trade deficit and strategic rivalry still complicating ties.

Beijing and New Delhi regularly accuse each other of trying to seize territory along their unofficial high-altitude demarcation line.

A deadly clash between soldiers from the two countries in 2020 on the border between Tibet and the Indian region of Ladakh left 20 dead on the Indian side and four among the Chinese.

Xi last visited India in October 2019, where he met with Modi.