What the government proposed
On 22 October 2026 the UK government published a white paper on critical undersea infrastructure security and resilience. It would replace the Submarine Telegraph Act 1885. Deliberate damage to subsea data or energy conveyance systems would carry up to 14 years in prison and unlimited fines. Reckless damage would carry up to 10 years and gross negligence up to 2 years. The Record reports that the 1885 Act caps deliberate damage at a £1,000 fine and five years in prison.
The paper goes well beyond sentencing. It proposes statutory security duties for subsea data providers and a power for the Secretary of State to direct cable and repair providers on national security grounds. It also proposes a separate notification-and-screening regime for fibre-optic sensing. The consultation closes at 11:59pm on 14 January 2027.
The strongest case for acting
The case for reform is strong. The white paper says subsea cables carry about 99% of the UK's international data traffic, and pipelines supply 74% of its gas. It counts 64 active cable systems landing in the UK. A statute whose top fine is £1,000 is not a deterrent against a state-linked actor, or against a negligent shipowner whose anchor causes tens of millions in damage.
The Estlink 2 power cable between Finland and Estonia was damaged on 25 December 2024. The Record cites grid operator Elering's repair estimate of €50–60 million. ERR reported that Elering and Fingrid withdrew their request to seize the Eagle S tanker because holding it would cost hundreds of thousands of euros a month. They planned a civil suit for repair costs that could take five to six years. Operators who foot the bill and wait years for compensation are the problem a modern statute should address. The white paper's consideration of a statutory route for recovering repair costs is a sensible response.
A culpability ladder is also better than a single blunt offence. Separating intent, recklessness and gross negligence lets prosecutors match the penalty to the conduct. The paper's proposed defences cover saving life, preserving a vessel, and inadvertent damage during repair. They are drafted with safeguards against shielding reckless conduct.
Where the proposals need discipline
The criminal tiers are the least contentious part. Three other parts need closer scrutiny.
Extraterritorial reach. The paper would apply the offences in UK territory, to UK nationals and UK-flagged vessels at sea, and beyond the territorial sea where effects are significant in the UK. The government itself acknowledges that state practice here is unsettled. A broad claim that is hard to enforce can chill lawful fishing, shipping and survey work without stopping a hostile state. The Eagle S episode shows how hard it is to turn a damaged cable into a durable prosecution or recovery. A larger penalty does not fix jurisdiction.
Penalty scale for operators. The security duties would be backed by fines of up to £10 million or 10% of qualifying worldwide revenue, whichever is higher. Directions would carry up to £17 million or 10% of global turnover, plus daily penalties. These figures mirror the telecoms security regime. They are heavy for the small and mid-sized operators and repair-vessel owners the paper expects to regulate. Revenue-linked ceilings suit global platforms, and they sit awkwardly on a specialist cable-repair firm whose business is capital-intensive and thinly margined. Detailed requirements are also to be set through secondary legislation and codes of practice. Operators therefore need clear statutory limits on what those codes can demand. The paper repeatedly commits to measures that are "appropriate and proportionate", and the bill should write that test into the text.
Fibre-optic sensing. This is the sharpest innovation question. The paper would cover distributed acoustic sensing, distributed temperature sensing and related techniques, with a list that can be amended by secondary legislation. Notification would be required at least six months before permanent deployment on existing infrastructure, and typically twelve months for new cables with integrated sensing. Screening could take up to six months. Existing deployments would have to be notified within 90 days of the law taking effect. The security rationale is plausible, since sensing can reveal vessel movements and infrastructure vulnerabilities. But sensing is also how operators detect anchor drags and fishing damage early, and how scientists monitor seismic activity. A year-long clock on beneficial resilience technology works against the paper's own goal. Low-risk uses, such as monitoring the operator's own cable on the operator's own fibre, should get a fast, light path.
What to push for in the consultation
The consultation poses 56 questions. Respondents should focus on four changes:
- Define "security compromise" narrowly enough that accidents handled with reasonable care are not criminalised.
- Keep the secondary-legislation power bounded by an express proportionality test and a duty to consult.
- Create a fast track for sensing that is defensive, operator-owned and limited in range.
- Match enforcement ceilings to operator size, and publish the cost evidence from the paper's accompanying survey before the bill is drafted.
The core policy is right. A cable system that carries almost all of the UK's international data should not be protected by a Victorian fine. The sensible reform would punish genuine sabotage and recklessness severely and leave lawful maritime and technology activity room to operate. The details in the final bill will decide whether it does that.