HANOI — Hanoi will soon have a credible naval deterrent to Beijing in the South China Sea in the form of Kilo-class submarines from Russia, which experts have said could make Beijing think twice before pushing its much smaller neighbour around in disputed waters.

A master of guerrilla warfare, Vietnam has taken possession of two of the state-of-the-art submarines and will get a third in November under a US$2.6 billion (S$3.3 billion) deal with Moscow in 2009. A final three are scheduled to be delivered in two years.

While both Vietnam and China are under communist rule and annual trade has risen to US$50 billion, Hanoi has long been wary of Beijing, especially over its claims to most of the potentially energy-rich South China Sea. Beijing’s placement of an oil rig in waters claimed by Hanoi earlier this year infuriated the latter, but coastguard vessels despatched by Vietnam to the platform were always chased away by larger Chinese boats.

… “Sea denial means creating a psychological deterrent by making sure a stronger naval rival never really knows where your subs may be,” said Mr Collin Koh of Singapore’s S Rajaratnam School of International Studies.