Vietnam nears completion of militarised South China Sea outposts — including airfields capable of hosting nuclear bombers

It had constructed roughly 70 per cent of the artificial landmass that China has built in the disputed archipelago by March this year, according to the Center for Strategic and International Studies' Asia Maritime Transparency Initiative.

This development "all but ensures that Vietnam will match – and likely surpass – the scale of Beijing's island-building," the think tank stated in a report published in August.

Satellite imagery captured this year showed infrastructure, including munitions storage containers, was beginning to appear on Vietnamese claimed reefs.

Militarisation of its outposts now includes ports, harbours and an 8,000-foot runway on Barque Canada Reef, Defence News reports.

Alexander Vuving, professor at Honolulu’s Asia Pacific Center for Security Studies, said the South China Sea is an "existential issue" for Vietnam.

"Vietnam right now is one of the major exporting nations in the world and 90 per cent of Vietnam’s foreign trade exports to the world go through the South China Sea," he told Defence News.

“The South China Sea is also important to Vietnam security-wise."

“The French came into Vietnam from the sea, and the Americans also came to Vietnam from the sea … now you have the Chinese threat.”

In February, China said it opposes Vietnam's construction activities on Barque Canada Reef, saying it was Chinese territory.

The South China Sea remains a subject of heavy contention, as China claims most of it.

But many of China's neighbours, including Vietnam and the Philippines contest these claims.

China sailed its largest and most advanced aircraft carrier through the South China Sea in September in a major show of force.

The Chinese navy claimed the journey by The Fujian had been conducted in order to carry out "scientific research and training missions".