China’s Undersea Cable-Cutting Technology
CHINA’S UNDERSEA CABLE-CUTTING TECHNOLOGY
INTRODUCTION
On 22 March 2025, the South China Morning Post (SCMP) reported that China had unveiled its new undersea cable-cutting technology. Such a disclosure has raised alarm and speculation that China might use the technology for geopolitical purposes and will harm 95% of the world’s internet connection.
BACKGROUND
2. China has unveiled its undersea cable-cutting technology, emphasising its primary application for civilian purposes, such as salvage operations and seabed mining. This Chinese technology distinguishes itself from earlier versions primarily due to its extraordinary depth capability, reaching up to 4,000 meters, which is double the operational range of existing subsea infrastructure and exceeds the publicly known capabilities of most other nations. The technology also incorporates advanced materials and design, including a diamond-coated grinding wheel and a titanium alloy shell with oil-compensated seals, enabling it to endure extreme pressure and efficiently cut armoured cables. China is the first country to officially introduce such a device, representing a significant advancement in deep-sea operations, developed by the China Ship Scientific Research Centre and the State Key Laboratory of Deep-Sea Manned Vehicles.
3. China’s decision to publicise this technology can be analysed from various perspectives. It showcases China's technological advancements and leadership in deep-sea engineering, potentially enhancing its position in global maritime affairs. Moreover, this capability carries strategic significance as it may affect global communication networks and shift maritime power dynamics, providing China with an advantage in geopolitical negotiations and conflicts. The introduction of this technology might also serve as a deterrent against interference with China's interests and strengthen its diplomatic leverage in international relations. Additionally, China may utilise it primarily as a tool for psychological deterrence and grey-zone coercion.
COMMENTS
4. The assumption that China may use its undersea cable technology for sabotage or geopolitical purposes is not unfounded. Taiwanese authorities recorded over twenty cable disruptions from 2023 to 2025. Among these incidents was the severing of a cable connecting the Penghu Islands in 2025, involving the Togo-flagged Hong Tai 58, which had a Chinese crew, as well as damage to cables near Keelung by the Tanzania-flagged Shunxin-39. In Europe, the Chinese bulk carrier Yi Peng 3 was suspected of cutting Baltic Sea cables in 2024. Separately, the NewNew Polar Bear container ship acknowledged damaging the Baltic connector pipeline in 2023 but blamed it on a storm. Beijing has denied any intent to cause harm, asserting that the incidents were accidents or a result of natural causes.
5. Looking ahead, to minimize the impact of sabotage, prompt repairs of damaged cables and rerouting of data traffic are essential. This will enhance the resilience of the undersea cable infrastructure. Detection-based deterrence is another crucial strategy to prevent sabotage. This involves leveraging advanced technologies such as quantum sensors, underwater robotics, and AI to increase visibility and prevent hostile actors from operating unnoticed.
6. Like any other country, Malaysia relies on undersea cables for power and communication. The deepest undersea cables in Malaysia and the surrounding region are not well-documented; typically, undersea cables are found at depths of less than 2,000 meters.
7. Therefore, the protection of undersea apparatus is vital. Given the circumstances, securing undersea cables involves multiple stakeholders from both government and private sectors. Thus, coordination and cooperation among relevant ministries and agencies are crucial. MINDEF and the Malaysian Armed Forces (MAF) must define their roles and responsibilities in safeguarding undersea cables. Simultaneously, MINDEF and MAF should learn from their foreign counterparts regarding military involvement in this matter.
8. In parallel, Malaysia should seize the opportunity to explore such technologies further. The introduction of this technology is groundbreaking, and Malaysia must leverage its close ties with China to gain knowledge, experience, and technical expertise in undersea cable cutting. This will enhance our deep-sea technology research and development, leading to new milestones in Malaysia-China relations. However, a crucial consideration that we should reflect upon is the ethical aspects of supporting such technology
9. Malaysia should also explore and develop new technologies that enable existing and dedicated undersea cables to monitor their environments for potential sabotage or damage by detecting disturbances through changes in light signals. This emerging acoustic sensing technology can provide early warnings to protect critical underwater internet infrastructure.
10. Therefore, Malaysia must remain vigilant to the potential threats posed by undersea cable-cutting technology. Nevertheless, Malaysia should also equip itself with similar technology and strengthen its ties with China.
Prepared by
Mr. Ahmad Tajuddin bin Mohd Said
Assistant Director
Contemporary Security
MiDAS
28 March 2025