Malaysia and Vietnam are two Southeast Asian countries with maritime boundaries which meet in the Gulf of Thailand and South China Sea.
In the South China Sea, Malaysia and Vietnam are involved in the multi-national claims over some of the Spratly Islands and adjacent waters.
Malaysia's claim is made through a territorial sea and continental shelf map published by its Mapping and Survey Department in 1979 showing the boundary, drawn as the equidistant line between Malaysia's Redang Island and the Vietnamese shore, ignoring islands off its coast.
[5] Malaysia and Vietnam both have overlapping claims in the South China Sea involving the continental shelf as well as the islands of the Spratly group.
Malaysia claims a portion of the South China Sea together with 11 islands and other marine features in the Spratly group on the basis that they are within its continental shelf.
It also claims two marine features currently occupied by Vietnam, namely Amboyna Cay and Barque Canada Reef.
[6] The "defined area" claimed in the joint submission covered a stretch of the South China Sea which lay in between the 200 nautical mile limit of the two countries.
The joint submission stated that the area was already subject to overlapping claims, including by both the submitting countries.
Nevertheless, Malaysian Prime Minister Najib Abdul Razak said the two countries had reached a broad understanding as to the apportionment of the defined area.
[7] China, which is one of the claimants of the Spratly Islands and its adjacent waters, lodged a note[6] with the UN Secretary-General on 7 May 2009 objecting to the extended continental shelf submission.
In its reply on 18 August 2009, Vietnam stated its legal right to lodge the submission and reasserted its "indisputable sovereignty" over the Spratly and Paracel Islands.
Malaysia also rejected the Philippines' assertion of sovereignty claims over North Borneo, pointing to the separate judgement of Judge Ad Hoc Franck in the Sipadan and Ligitan Case of the International Court of Justice.
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