China sending an oil rig to waters disputed with Vietnam is a move to assert its legal claim and practical hold over contested territory whatever the short-term political and diplomatic costs, analysts say — but could play into Washington’s hands.

Beijing’s controversial move to dispatch the deep-water rig along with a reported 70 vessels triggered clashes in the South China Sea, just after a visit to the region by US President Barack Obama and ahead of this weekend’s Association of Southeast Asian Nations (Asean) summit.

It also comes amid heightened tensions between Beijing and Manila, which has asked a United Nations tribunal to rule on China’s claims over most of the sea. Beijing — which prefers to negotiate directly with its smaller, weaker neighbours — has vehemently rejected arbitration.

Experts say that while Beijing has cast the drilling operation by state-owned CNOOC as part of its long-term oil exploration programme, energy resources are probably a secondary consideration.

Read more: http://www.bangkokpost.com/news/asia/409142/vietnam-sea-spat-part-of-china-larger-strategy-experts