Are China and Vietnam on collision course over Beijing’s ‘creeping’ demarcation in Gulf of Tonkin?
- Beijing’s move to set a baseline in the Gulf of Tonkin is a sign of its aim to assert greater control in the strategically important area
- The demarcation could also be an ‘inevitable step’ towards the disputed Spratly Islands being the next area where Beijing wants to set its lines

Analysts say China’s move may not comply with international maritime conventions, adding that Beijing’s “creeping” encroachment shows that it is aiming to assert greater control over an important body of water.
On March 1, Beijing released a statement showing a set of seven base points that, when connected, form the baseline for its territorial claims in the Gulf of Tonkin, known as Beibu Gulf in China.
The demarcation is in line with the Law on the Territorial Sea and Contiguous Zone promulgated by China in 1992, according to Chinese state tabloid The Global Times, citing the ministry’s Department of Boundary and Ocean Affairs.
The department said on its official WeChat account that the move was necessary to exercise China’s sovereignty and jurisdiction.