WASHINGTON - China appears to be within two years of deploying submarine-launched nuclear weapons, adding a new leg to its nuclear arsenal that should lead to arms-reduction talks, a draft report by a congressionally mandated US commission says.

China is alone among the original nuclear weapons states to be expanding such deterrent forces, the US-China Economic and Security Review Commission said in a draft of its 2012 report to the US Congress.

Beijing is "on the cusp of attaining a credible nuclear triad of land-based intercontinental ballistic missiles, submarine-launched ballistic missiles, and air-dropped nuclear bombs," the report says.

China has had a largely symbolic ballistic missile submarine capability for decades but is only now set to establish a "near-continuous at-sea strategic deterrent," the draft said.

The deployment of such a hard-to-track submarine-launched leg of China's nuclear arsenal could have significant consequences in East Asia and beyond. It also could add to tensions between the United States and China.