Taipei: China could block undersea cable repair vessels if a conflict across the Taiwan Strait were to occur, a major problem for Taiwan given that more than 90 percent of its internet connectivity depends on submarine cable links, a report by intelligence advisory firm Recorded Future has said.
According to Focus Taiwan, the report titled “Submarine Cables Face Increasing Threats Amid Geopolitical Tensions and Limited Repair Capacity” was released by Recorded Future’s intelligence research unit Insikt Group on July 17. Insikt based its conclusion on an analysis of recent territorial conflicts between China and the Philippines in the South China Sea, where the China Coast Guard (CCG) has attempted to block Philippine resupply operations to vessels at key shoals.
The CCG and other Chinese forces have a history of interfering with vessels from other claimants in the South China Sea and with vessels operated by powers outside the region, such as the United States. “These incidents suggest that Beijing could take similar action to block repair vessels from accessing damaged submarine infrastructure in the event of a potential escalation of tension or outbreak of hostilities around Taiwan,” the research group stated.
The report highlighted concerns over Chinese actions potentially damaging undersea cables around Taiwan, citing an incident with the Taiwan-Matsu No. 3 fiber-optic cable. Although the repairs were completed by Chunghwa Telecom Co. in early March, Taiwan’s Ministry of Digital Affairs attributed the damage to “natural deterioration.”
However, frequent issues with undersea cables in waters around Taiwan have led to speculation of China engaging in “gray zone” activities targeting Taiwan’s telecommunications connections. The report noted incidents in 2024 and 2025 involving damage to submarine cables in the Baltic Sea and around Taiwan, with some linked to suspicious vessel activities.
The expanding role of Chinese companies in deploying and operating submarine cables raises espionage concerns for countries using them. The report suggested that China’s preparations for a possible military incursion into Taiwan and deteriorating U.S.-China relations likely incentivize physical attacks and intelligence collection efforts targeting the submarine cable system.
To address these challenges, the research group recommended conducting comprehensive stress tests to improve resilience and guard against prolonged connectivity issues. It also emphasized the importance of addressing factors such as lack of redundancy and limited repair capacity that could exacerbate the impact of submarine cable damage.