A recent case in Taiwan involved a Chinese captain sentenced to three years for intentionally damaging undersea cables, underscoring the challenges of proving intent in such legal matters.

A UK government submission to Parliament revealed that the country has limited capabilities to monitor maritime traffic around undersea cables, covering only 22% of its exclusive economic zone.

The UK's strategic defense review has highlighted the vulnerability of undersea cables, noting that the country is home to 60 cable systems, including nine of the 15 connections between North America and Europe.

A report from the China Strategic Risks Institute (CSRI) warns that the UK is 'woefully' unprepared for increasing sabotage threats to these undersea cables from China and Russia.

The report suggests possible coordination between China and Russia in targeting undersea cables, with incidents reported in the Baltic Sea and near Taiwan.

Between January 2021 and April 2025, 12 incidents of suspected undersea cable sabotage were investigated, with 10 cases linking the activities to vessels associated with China or Russia.

The involvement of 'shadow fleet' vessels aligns with a broader 'grey zone' strategy employed by these nations, aimed at coercing adversaries without provoking direct conflict.

In response to recent incidents of cable damage, NATO Baltic states have pledged to enhance patrol missions, suspecting Russian involvement.

As a vital hub for Euro-Atlantic cable infrastructure, the UK is expected to be a frequent target for future sabotage operations.

Undersea cables are crucial for global connectivity, handling up to 99% of intercontinental data transmission, which is essential for various sectors including banking and global logistics.

Andrew Yeh, CSRI's executive director, emphasized the need for the UK to enhance its monitoring and surveillance capabilities to counter grey-zone tactics.

The Department for Science, Innovation and Technology has expressed challenges in identifying abnormal maritime activity due to the high volume of traffic in these waters.