U.K. calls for 'toll-free' Strait of Hormuz
The British Foreign Secretary held diplomatic talks with Iran's Foreign Minister, urging Iran to keep the Strait of Hormuz open for global trade without impo...
What Happened
- The British Foreign Secretary held diplomatic talks with Iran's Foreign Minister, urging Iran to keep the Strait of Hormuz open for global trade without imposing transit tolls or other restrictions.
- The UK stated it is working to build a "global alliance in support of freedom of navigation" through the Strait of Hormuz.
- Iran has signalled, through a parliamentary member, that commercial vessels may be required to pay tolls for passage — a position the International Maritime Organization (IMO) has called illegal.
- The IMO's Secretary-General stated that countries do not have the right to introduce tolls or charges on international straits, positioning Tehran's toll proposal as a violation of international maritime law.
- Amid the standoff, the status of the strait remains fluid: Iran's government has alternately declared it "open" and "closed," while the IRGC has continued interdicting vessels attempting to transit.
Static Topic Bridges
Freedom of Navigation — UNCLOS Transit Passage Regime
The United Nations Convention on the Law of the Sea (UNCLOS, 1982, in force 1994) created a distinct legal category — "transit passage" — specifically for straits used for international navigation. Part III of UNCLOS (Articles 34–44) governs this regime and was an innovation of the Third UN Conference on the Law of the Sea (UNCLOS III, 1973–1982).
- Article 38(1): All ships and aircraft enjoy the right of transit passage through straits used for international navigation — a continuous, expeditious, and unobstructed transit.
- Article 38(2): Transit passage cannot be suspended by the bordering state, unlike innocent passage (Article 17–25), which coastal states can temporarily suspend for security.
- Article 44: Bordering states "shall not hamper transit passage" and must give appropriate publicity to any danger to navigation within the strait — but cannot impose fees, tolls, or conditions on transiting vessels.
- Critically, Iran has signed but NOT ratified UNCLOS, and has reserved its position on the transit passage regime, arguing it applies only between states that have mutually ratified UNCLOS.
Connection to this news: The UK's demand for "toll-free" passage directly invokes the Article 44 prohibition on levying charges on transiting vessels. The legal dispute arises from Iran's non-ratification of UNCLOS, which it uses to justify its assertion that the strait falls under its territorial sea jurisdiction, where different — and more restrictive — rules apply.
International Maritime Organization (IMO) — Role and Mandate
The International Maritime Organization is the United Nations specialised agency responsible for the safety, security, and environmental regulation of international shipping. Established under the Convention on the International Maritime Organization (adopted 1948, in force 1958), the IMO has 175 member states and is headquartered in London.
- The IMO's core legal framework for navigation includes the International Regulations for Preventing Collisions at Sea (COLREGS, 1972), SOLAS (Safety of Life at Sea, 1974), and MARPOL (Marine Pollution, 1973/78).
- The IMO does not have enforcement powers — it sets standards and frameworks, while flag states are responsible for enforcement on their flagged vessels.
- The Strait of Hormuz falls under IMO-designated Traffic Separation Schemes (TSS), which define the two-mile inbound and two-mile outbound shipping lanes separated by a buffer zone.
- The IMO's Legal Committee has consistently held that transit passage through international straits is a customary international law norm that cannot be restricted through national legislation or tolls.
Connection to this news: The IMO Secretary-General's public statement that toll-charging on international straits is "illegal" strengthens the international coalition the UK is attempting to build, by grounding the toll-free demand in multilateral institutional authority rather than bilateral geopolitics.
UK's Strategic Interest — Persian Gulf and Freedom of Navigation
The United Kingdom has maintained a military and diplomatic presence in the Persian Gulf since the withdrawal of forces "East of Suez" in 1971. The UK contributes to the Combined Maritime Forces (CMF) — a 38-nation naval partnership headquartered in Bahrain — which conducts maritime security operations in the Persian Gulf, Gulf of Oman, Red Sea, and Indian Ocean.
- The UK has naval assets under Operation Kipion (Persian Gulf), which has been active since 1980.
- Under Operation Sentinelle (2019–), UK warships accompany British-flagged vessels through the Strait of Hormuz following Iran's seizure of the Stena Impero tanker in 2019.
- The Combined Maritime Forces includes the US Fifth Fleet and operates under Combined Task Force (CTF) 151 (counter-piracy), CTF 152 (Arabian Gulf security), and CTF 153 (Red Sea security).
- UNCLOS Article 37: The Strait of Hormuz qualifies as an international strait as it connects the Persian Gulf (a semi-enclosed sea) to the Gulf of Oman and Arabian Sea — both high seas or EEZ waters.
Connection to this news: The UK's diplomatic push reflects both legal principle and commercial self-interest: as a major financial and maritime trading nation, British-flagged and British-insured vessels (Lloyd's of London underwrites a significant share of global shipping) face direct risk from any closure or toll regime in the strait.
Iran's Legal Position — Sovereignty Claims and the Strait
Iran maintains a distinctive legal position on the Strait of Hormuz. Both Iran and Oman border the strait, and the strait falls within their overlapping 12-nautical-mile territorial sea zones. Iran argues that since it has not ratified UNCLOS, the transit passage regime does not bind it, and the strait should be governed by the older 1958 Convention on the Territorial Sea, which gave coastal states broader control.
- Under the 1958 Convention, only "innocent passage" is guaranteed — and can be suspended for security reasons (unlike transit passage under UNCLOS).
- Iran and Oman are both coastal states of the strait; Oman has ratified UNCLOS and supports transit passage rights.
- Iran's Constitution (Article 153) prohibits any agreement that establishes foreign domination over Iranian territory — used domestically to justify resistance to internationally-asserted navigational rights.
- Iran has in the past (2011, 2012) threatened to close the strait in response to Western sanctions on its oil sector.
Connection to this news: Iran's assertion that it can impose tolls flows directly from its claim to treat the strait as territorial sea subject to 1958 Convention rules rather than UNCLOS transit passage rules — a distinction with enormous commercial and legal consequences for global shipping.
Key Facts & Data
- Strait of Hormuz: ~21 nautical miles at narrowest; two-mile-wide shipping lanes (inbound and outbound)
- UNCLOS adopted: 1982 (Montego Bay); in force: November 16, 1994; parties: 168 states
- Iran: signed UNCLOS but has NOT ratified it
- IMO established: 1948 (Convention adopted); in force: 1958; 175 member states; HQ: London
- UK's Operation Kipion (Persian Gulf): active since 1980
- Combined Maritime Forces (CMF): 38-nation naval coalition, HQ Bahrain (US Fifth Fleet)
- UNCLOS Article 44: prohibits bordering states from hampering transit passage or imposing charges
- 1958 Geneva Convention on the Territorial Sea: allows suspension of innocent passage for security — Iran's preferred legal framework
- ~20 million barrels/day transited Hormuz before the 2026 crisis