Vietnam is fighting against Beijing's supremacy in the South China Sea by building its own islands and military bases in the disputed waters, according to a new report.

The Asia Maritime Transparency Initiative (AMTI), run by the Centre for Strategic and International Studies, reported that Vietnam has been dredging earth and sand and adding to the surface areas of at least eight pieces of land it controls in the southeast quarter of the South China Sea since the beginning of 2025.

It is the latest attempt to push back against China, which has for years laid a claim to a massive swathe of the sea.

Beijing claims almost all of the 1.2million square miles of the South China Sea, a body of water vitally important to global trade and security, belong to it.

It bases its claim on the 'Nine Dash Line', based on historical claims that international courts have ruled are bogus.

China has long built up runways and military installations across the sea to beef up its claim, moves that its rivals haven't taken kindly to.

Hanoi hasn't explicitly fought against China's attempts at regional domination in the past, so its latest move in the Spratly Chain, an an archipelago of about one hundred islands, is the boldest action it has taken against Beijing.

Dredging and landfill work has taken place at Alison Reef, Collins Reef, East Reef, Landsdowne Reef, and Petley Reef, all of which had previously housed only small concrete pillbox structures, according to AMTI.

Meanwhile, military infrastructure has been sighted on Barque Canada Reef, Discovery Great Reef, Ladd Reef, Namyit Island, Pearson Reef, Sand Cay, and Tennent Reef.

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Landsdowne Reef, one of the islands Vietnam has been extending

Collins Reef, one of the islands Vietnam has been adding earth and sand to

On each reef, munitions storage facilities can be seen. Each reef is now also home to a recurring group of six buildings, the purpose of which is not yet known.

The AMTI believes Vietnam is now building a runway on Barque Canada Reef.

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China has expressed its anger at the latest developments, with a spokesperson for its ministry of foreign affairs saying: 'The Spratly Islands are China's inherent territory.

'China firmly opposes relevant countries' construction activities on illegally occupied islands and reefs.

'China will take necessary measures to safeguard its territorial sovereignty and maritime rights and interests.'

The latest beef comes just weeks after dramatic footage showed the terrifying moment two Chinese vessels smashed into each other while chasing a Philippine patrol boat in the South China Sea.

The navy and coastguard ships collided near the contested Scarborough Shoal, an atoll around 140 miles east of the main Philippine island of Luzon and more than 500 miles southeast of Hong Kong.

The collection of reefs, rocks and a lagoon - covering around 58 square miles - has historically been claimed by both China and the Philippines.

The crash happened as the Philippine Coast Guard (PCG) was escorting boats distributing aid to fishermen in the area, PCG spokesperson Commodore Jay Tarriela said.

He added the Chinese Coastguard (CCG) vessel 3104 was 'chasing' the Philippine craft, known as the BRP Suluan, 'at high speed'.

Vietnam has been adding usable land to East Reef, one of the Spratly Islands

A Philippine Navy AW-109 Helicopter lands on the deck of a Philippine warship, as part of the Balikatan's multilateral maritime exercise involving Japanese and American warships, in West Philippine Sea, Philippine, on April 24, 2025

China's third aircraft carrier, the Fujian, prepares to set out for maiden sea trials from Shanghai Jiangnan Shipyard in eastern China's Shanghai, Wednesday, May 1, 2024

It soon 'performed a risky manoeuvre' from the starboard side of the Philippine vessel, he continued, 'leading to the impact with the PLA [People's Liberation Army] Navy warship'.

CCG crew members were visible on the front of the craft - the section that hit the battleship - just moments before the collision, he said. Their fate is not known.

The CCG vessel was 'rendered unseaworthy' in the smash, which appeared to happen incredibly close to the PCG craft.