(UPDATE) THE US will 'surely invoke' its Mutual Defense Treaty (MDT) with the Philippines if an armed attack against the country's 'assets, including those of the Philippine Coast Guard (PCG), is committed in the South China Sea,' a US official told a congressional hearing in Washington early Friday.

Lindsey Ford, deputy assistant secretary of the US Defense Department, gave this assurance before the US House of Representatives, which tackled China's continued aggression in the waters, including laser pointing and water cannon attacks against Philippine personnel.