Which line divides two countries India and China? And what is the history of this line?

Question

China has blocked a tributary as part of the construction of its "most expensive" hydro-power project that could cause concern in India as it may impact water flows into the lower riparian countries.

What is the name of tributary and main river?

Answer 1

The McMahon Line is a line agreed to by Britain and Tibet as part of the Simla Accord, a treaty signed in 1914. It is the effective boundary between China and India, although its legal status is disputed by the Chinese government.

The line is named after Sir Henry McMahon, foreign secretary of the British-run Government of India and the chief negotiator of the convention at Simla. It extends for 550 miles (890 km) from Bhutan in the west to 160 miles (260 km) east of the great bend of the Brahmaputra River in the east, largely along the crest of the Himalayas. Simla (along with the McMahon Line) was initially rejected by the Government of India as incompatible with the 1907 Anglo-Russian Convention.