The US, Japan, Australia and India are joining forces to track the movements of shipping’s dark fleet in the Indo-Pacific region.

The so-called Quad group has unveiled a satellite-based initiative that it says will help tackle human and weapons trafficking, illegal fishing and Chinese maritime militias.

The Quad believes these militias, while purporting to be engaged in commercial fishing, instead enable Chinese coast guard and naval activity.

“This addresses a real need ... from almost across the region, be it from South East Asia, be it in the Pacific, be it in south Asia, which is for much better maritime domain awareness,” a senior US official told the Financial Times.

The scheme will give the group the ability to know what is happening in countries’ territorial waters and in their exclusive economic zones, the official added.

The Indo-Pacific Partnership for Maritime Domain Awareness was announced at a Quad summit in Tokyo this week.

The four countries will provide funding to work with a commercial satellite-based tracking service that would offer nearly real-time maritime intelligence to other nations, the report said.

Radio frequencies and radar signals would be monitored to allow tracking of vessels that have turned off AIS transponders to avoid detection.

A “rogue” fleet of tankers that go dark to trade in sanctioned Iranian and Venezuelan oil has long angered mainstream shipowners, who want these elderly vessels scrapped.

The US official added that the service is an effective, relatively low-cost solution.

The information would be shared through centres in India, Singapore, Vanuatu and the Solomon Islands.

The announcement came a day after President Joe Biden said the US would use force to help defend Taiwan from any attack by China.

This appeared to run counter to a long-held US policy of refusing to make clear whether it would come to the island nation’s aid. The White House, however, later said the policy had not changed.