And, experts warn, these talks – part of a highly calculated geopolitical effort by US allies – could reinforce the so-called first island chain and restrict Beijing’s naval access in an area vital to any potential conflict over Taiwan: its clear red line.

Tensions have sharpened since Japan and the Philippines announced last week that they would begin formal negotiations to delimit the maritime boundary of their exclusive economic zones (EEZs) and continental shelves – a zone that significantly overlaps with Taiwan’s to the east of the island.

Under international law, coastal states hold EEZ rights up to 200 nautical miles (230 miles) from their shores. That includes sole authority over natural resources and full control over artificial installations. The legality of foreign military activities within those waters remains fiercely contested.

The launch of the delimitation talks would be seen in Beijing as an attempt to challenge its position on Taiwan, according to Ding Duo, director of the Centre for International and Regional Studies at the National Institute for South China Sea Studies, a government-sponsored think tank.

Crucially, a bilateral agreement extending into waters claimed by third parties carries no legal weight for excluded claimants.