The number of high-risk vessels flying African flags has surged, increasing risks to legitimate shipping interests and foreign investment.

Sweden recently intercepted two cargo ships believed to be part of the Russian shadow fleet. One was flying a Comorian flag; the other a Guinean flag. Swedish authorities believe the flags were used fraudulently – a common tactic deployed by criminal networks.

Global shipping data over the past year has revealed a surge in the number of vessels flying African flags, particularly those connected to shadow fleet networks.

These networks are loosely organised groups of tankers and cargo vessels used to circumvent international sanctions or trade blockades. Shadow fleets often operate under obscured ownership and deploy evasion tactics such as ship-to-ship cargo transfers in international waters and manipulation or deactivation of automatic identification system transponders to mask movement. The vessel’s flag is another key instrument for avoiding sanctions.

Under international law, every merchant ship operating beyond national waters must fly a flag. In return for a fee, the flag state assumes jurisdiction and regulatory responsibility over the vessel, thereby limiting other countries’ ability to board, detain or enforce their laws against it on the high seas.

Oversight by flag states varies, however. Some shipowners flag their vessels in registries known for weak oversight, simplified procedures, lower fees and lighter compliance burdens. This is legal, but such ‘flags of convenience’ can create regulatory gaps that are sometimes exploited for illicit purposes.

And although sanctions evasion by sea is not new, there has been a marked escalation in the scale and sophistication of shadow fleet operations. In particular, recent sanctions targeting major oil exporters have intensified incentives to sustain seaborne exports despite shipping restrictions, leading to investment in alternative maritime networks to keep the oil flowing.

Tighter scrutiny by established flag states has prompted shadow fleet operators to seek alternative registries in Africa. Apart from Liberia, the continent has been a marginal player in the global ship registration system.

Over several years, registries in Benin, The Gambia, Comoros, Guinea and Sierra Leone have seen exponential increases in registered tonnage. In Cameroon alone, the ship registry has increased by 126% over the past year, allegedly due to the rapid listing of high-risk tankers linked to the Russian shadow fleet.

Of greater concern are vessels that lack legal registration or fraudulently use a country’s flag. Earlier this year, Germany identified the tanker Range Vale as part of Russia’s shadow fleet, after it falsely claimed registration in Zimbabwe. Zimbabwe then notified the International Maritime Organization (IMO) that a fraudulent entity had issued the certificates. The ship continues to operate, now flying Sierra Leone’s flag.

Many African countries don’t operate international registries. After eight recorded incidents of fraudulent use of its flag, Malawi informed the IMO that it does not offer international flagging. In 2024, the IMO found that all Eswatini flags were false after several ships claimed registration with the country. Eswatini doesn’t have a flag registry and is not an IMO member.

The organisation last month confirmed that over half of all reported false-flag cases involved African flags. Eighty-three tankers, general cargo ships and container ships reportedly claimed to be registered in Comoros – the most popular flag on the list.

Is this trend a choice by sanctions-busting countries? Or are African states being exploited by intermediaries and private registry operators? It’s not uncommon for companies to run national ship registries on behalf of governments, opening the door to fraud if proper oversight is lacking.

Nevertheless, it is clear that African flags – legal or illegal – offer limited oversight and enforcement capacity compared to established registries. Maritime compliance agencies must contend with vessels whose ownership is often unverified, making it difficult to identify and monitor unscrupulous actors.

African registries are also less likely to appear on the radar of major port state control regimes, insurers or international monitoring programmes, offering a low-profile option for vessels seeking to circumvent stricter controls.

This has two important implications for African states. First, countries perceived as facilitating sanctions evasion may face enhanced port state inspections, insurance restrictions or diplomatic pressure, potentially affecting legitimate shipping interests, trade costs and foreign investment.

Second is maritime safety – an often-overlooked issue. As shadow fleet vessels in the Baltic, Mediterranean and Black Seas face increased scrutiny, ships in the network may reroute around the notoriously challenging Cape of Good Hope.

Many of these vessels, some flying African flags, are ageing, poorly maintained and lack proper insurance. This raises the risk of environmental disasters in African waters and complicates legal liability and compensation in the event of an incident.

African states must avoid becoming unwitting enablers or deliberate facilitators of illicit maritime activity. Allowing a flag to be used for nefarious purposes damages perceptions of governance and trustworthiness. Even when private intermediaries are involved, ultimate responsibility rests with governments.

Several African states have initiated reviews and reforms in response to international pressure and criticism. Cameroon’s Prime Minister Joseph Dion Ngute announced plans to purge the national ship registry of vessels suspected of belonging to the shadow fleet and to strengthen oversight and regulatory controls.

Similar processes are occurring in Comoros, while Madagascar has initiated a monitoring system to improve fraud detection and authentication. But more must be done to ensure African flags are not misused.

First, African states should strengthen registry governance, including ensuring that new vessels meet safety, environmental and legal requirements. Second, they should regularly audit private registry operators, mandate transparent disclosure of ownership, and align flagging procedures with international best practices.

Finally, enhanced cooperation with regional maritime security initiatives and information-sharing platforms would enable African states to identify high-risk vessels before registration.

These steps can protect countries’ reputations, reduce exposure to illicit activity and ensure shadow fleets do not exploit their flags.

Written by Denys Reva, Researcher, Transnational Threats and Organised Crime, ISS Pretoria & Colleen Jacka, Founding Editor, Maritime Review Africa