Malaysia on Wednesday joined India in protesting a new Chinese map that lays claim to India’s territory and Malaysia’s maritime areas near Borneo island ahead of next week's Group of 20 summit in New Delhi.
This has exacerbated the tensions between China and India, which are embroiled in a three-year military standoff along their shared border.
The timing of the protest is key, as Chinese President Xi Jinping is expected to attend the summit.
"We reject these claims as they have no basis. Such steps by the Chinese side only complicate the resolution of the boundary question," India's External Affairs Ministry spokesman Arindam Bagchi said in a statement late Tuesday.
Malaysia's foreign ministry in a statement Wednesday rejected China’s "unilateral claims" and added the map is "not binding" to the country.
It also called for the conflict to be handled in a peaceful and rational manner through dialogue and negotiations.
India on Tuesday formally lodged an objection through diplomatic channels with the Chinese side on the so-called 2023 "standard map" that lays claim to India’s territory.
The version of the Chinese map published Monday on the Ministry of Natural Resources website clearly shows Arunachal Pradesh and the Doklam Plateau, over which the two sides have feuded, included within Chinese borders, along with Aksai Chin in the western section that China controls but India still claims.
Indian External Affairs Minister Jaishankar Subhramanyam also dismissed China’s claim in a television interview on Tuesday night.
"Making absurd claims on India’s territory does not make it China’s territory," he said.
China recently refused to stamp out visas on the passports of officials from Arunachal Pradesh state in India's northeast, using a stapled-in certificate instead, implying the Chinese claim on the territory.
It also refuses to recognize India’s sovereignty over the part of Kashmir it controls and declined to send a delegation to a G20 meeting over there in May.
Last week, Indian Prime Minister Narendra Modi informally spoke to China’s President Xi on the sidelines of the BRICS summit in Johannesburg, where the premier highlighted New Delhi's concerns about their unresolved border issues.
India's foreign ministry said the two leaders agreed to intensify efforts to de-escalate tensions at the disputed border and bring home thousands of their troops deployed there.
The disputed boundary has led to a three-year standoff between tens of thousands of Indian and Chinese soldiers in the Ladakh area. A clash three years ago in the region killed 20 Indian soldiers and four Chinese.
"The two sides should bear in mind the overall interests of their bilateral relations and handle properly the border issue so as to jointly safeguard peace and tranquility in the border region," the Chinese Foreign Ministry said after the two leaders' meeting.
Indian and Chinese military commanders had met earlier this month in an apparent effort to stabilize the situation.
A border, dubbed the "Line of Actual Control," separates Chinese and Indian-held territories from Ladakh in the west to India’s eastern state of Arunachal Pradesh, which China claims in its entirety.
India and China had fought a war over their border in 1962. China claims some 35,000 square miles of territory in India’s northeast, including Arunachal Pradesh with its mainly Buddhist population.
India says China occupies 15,000 square miles of its territory in the Aksai Chin Plateau, which India considers part of Ladakh, where the current faceoff is happening.