Vietnam Announces A Baseline To Determine Its Territorial Waters In Gulf Of Tonkin – OpEd |
The Vietnamese Government issued on Feb.21 a declaration establishing the baseline for measuring the breadth of Vietnam’s territorial waters in the Gulf of Tonkin, the VnExpress newspaper reported.
The declaration, announced by the Ministry of Foreign Affairs, follows Resolution No. 68 dated Feb. 14, 2025 of the National Assembly Standing Committee.
According to the Reuters news agency, Vietnam’s foreign ministry published a map defining its baseline claim in the Gulf of Tonkin, where it shares a maritime border with China, which it said on Feb.21 was to help protect and enforce its sovereign rights.
Baselines, according to the Reuters, are used to determine limits to territorial waters and exclusive economic zones, and are a sensitive subject in the South China Sea, where China, Vietnam and other countries in the region have some conflicting claims.
The ministry marked the line on a map with 14 points running from offshore Quang Ninh province to Quang Tri province.
The baseline “creates additional legal basis to protect and enforce Vietnam’s sovereignty, sovereign rights and jurisdiction, serving economic development, marine management, and promoting international cooperation,” the ministry said in a statement.
It said the baseline is the basis for determining the boundaries and scope of Vietnam’s maritime zones according to the provisions of United Nations Convention on the Law of the Sea (UNCLOS) and the Agreement on the Delimitation of the Gulf of Tonkin signed between Vietnam and China in 2000.
China’s foreign ministry didn’t immediately respond to a Reuters request for comment.
In March last year, China announced its baseline in the Gulf of Tonkin, and in response Vietnam said international law and the rights and interests of other countries must be respected.
The baseline, according to the VOV website, used to determine the width of Vietnam’s territorial sea in the Gulf of Tonkin consists of straight-line segments connecting a series of islands and islets, including Con Co Island, Gio Lon Islet, Chim Islet, Bo Cat Islet, and Tra Co Island, as well as Point No. 1 under the Agreement on the Delimitation of the Territorial Sea, Exclusive Economic Zone, and Continental Shelf between Vietnam and China in the Gulf of Tonkin.
According to the announcement, the baseline for calculating the width of the territorial sea of Bach Long Vi Island is defined as the lowest low-water line along the island’s coastline.
The outer boundary of Vietnam’s territorial sea in the Bac Luan estuary area is determined by nine points along the maritime boundary delimitation between Vietnam and China in the Gulf of Tonkin, with Point No. 10 specifically located within Vietnam’s waters.
The establishment of the baseline in the Gulf of Tonkin is intended to fulfill Vietnam’s rights and obligations under the provisions of the 1982 UNCLOS and is in accordance with Vietnam’s 2012 Law of the Sea.
The baseline used to determine the width of Vietnam’s territorial sea in the Gulf of Tonkin is defined based on UNCLOS regulations, taking into account the geographical and natural characteristics of the area, without affecting international treaties to which Vietnam is a party or member.
This baseline serves as the foundation for determining the boundaries and scope of Vietnam’s maritime zones in accordance with UNCLOS and the 2000 Gulf of Tonkin Delimitation Agreement between Vietnam and China. It further strengthens Vietnam’s legal basis for protecting and exercising sovereignty, sovereign rights, and jurisdiction while supporting economic development, maritime management, and international cooperation.
According to the VnExpress, the establishment of the baseline in the Gulf of Tonkin aims to exercise Vietnam’s rights and obligations under the 1982 United Nations Convention on the Law of the Sea (UNCLOS) and aligns with the 2012 Law of the Sea of Vietnam.
It provides a robust legal framework for protecting and excercising Vietnam’s sovereignty, sovereign rights, and jurisdiction, serving economic development and maritime management, and promoting international cooperation.
According to the Radio Free Asia website,The Chinese military has announced a live-fire exercise in an area in the Gulf of Tonkin from Monday to Thursday this week, warning ships not to enter the zone.
The warning came as Vietnam issued a formal map defining the baseline to demarcate its territory in the gulf. Though neither side linked their action to that of the other, it was unlikely to be a coincidence, some observers said.
China’s exercise comes amid the latest wrangle between the neighbors over Vietnam’s island building in the Spratly archipelago in the South China Sea.
“The establishment of the baseline in the Gulf of Tonkin aims to uphold Vietnam’s rights and obligations,” the Radio Free Asia reported quoting the Vietnamese foreign ministry’s statement, “It provides a robust legal basis for safeguarding and exercising Vietnam’s sovereignty, sovereign rights and jurisdiction.”
China has yet to comment on its neighbor’s announcement but some Vietnam watchers said China’s live-fire drills appeared to be a response to Vietnam’s baseline.
“Although the exercise area off northwest Hainan island is relatively far from Vietnam’s waters, the timing seems too close to be a pure coincidence,” the Radio Free Asia reported quoting Song Phan, a maritime researcher, as saying.
The new baseline that runs along Vietnam’s coast “conforms strictly to UNCLOS unlike the Chinese baseline,” he said.
Both China and Vietnam, however, have yet to renegotiate a joint fishery cooperation agreement in the Gulf of Tonkin after the old one expired in 2020.