Iran and the United States of America (U.S.), within the framework of the negotiation process conducted through Pakistan’s mediation, reached a 14-article memorandum on 14 June that envisaged the cessation of the war and the resolution of disputes between the parties through negotiations. The memorandum, named the “Islamabad Memorandum,” was digitally signed by Iranian President Masoud Pezeshkian and U.S. President Donald Trump on 18 June and entered into force.[i] Although the Iranian Army announced that it had closed the Strait of Hormuz again, stating that Israel’s attacks on Lebanon constituted a violation of the memorandum of understanding reached with the U.S.,[ii] the American side maintains that the strait is not completely closed and that vessel movements continue to a certain extent.[iii] In addition, while the U.S. Central Command (CENTCOM) has announced that the naval blockade imposed on Iranian ports has been lifted, American warships continue to remain in the region and maritime security patrols are ongoing.
Despite the crisis of confidence created by Israel’s operations in Lebanon, the technical talks planned to be held between the U.S. and Iran in Bürgenstock, Switzerland,[iv] have not been completely cancelled, but have been postponed to a later date. While the parties appear to preserve their will to continue the negotiation process, the success of the talks seems to depend largely on developments on the Lebanese front and on the implementation of confidence-building measures regarding the reopening of the Strait of Hormuz. From a maritime perspective, markets are now focused not so much on whether the talks will take place, but on whether concrete decisions will emerge from the talks regarding mine clearance in Hormuz, transit corridors and insurance risks.
The memorandum includes articles such as the opening of the Strait of Hormuz and the lifting of the U.S. naval blockade on Iran. With regard to the passage of ships stranded in Hormuz, Article 5 states that Iran “shall ensure the safe passage of commercial vessels from the Persian Gulf to the Gulf of Oman and vice versa free of charge for 60 days.” The same article also states that commercial shipping will begin immediately and will be fully restored within 30 days, depending on mine-clearing operations to be carried out by Iran. If these provisions are implemented, and if agreement is also reached on them during the Switzerland talks, possible scenarios concerning mine-clearing activities are examined in the following sections.
Although the coordinates of the mines or the exact minefields have not been published in open sources, Reuters,[v] and U.S. Navy sources have indicated that the risk is concentrated particularly around the existing International Maritime Organization (IMO)-approved Traffic Separation Scheme (TSS) in Hormuz, and that at certain times ships were even advised to avoid the TSS. In addition, there are also reports suggesting that during the crisis Iran published alternative traffic arrangements in order to prevent collisions with mines, thereby implying that the existing main traffic corridor could be risky. This raises the possibility that the mines may be located on or near the separation line, or in positions that could threaten the TSS.
In Reuters’ analyses on mine clearance,[vi] it is stated that the type of mines used by Iran in the region is not limited to bottom mines, but also includes drifting mines and tethered mines. In particular, tethered mines may break free due to reasons such as the rupture of the mooring chain, the effects of surface and bottom currents without a fixed pattern in the region, and similar factors, and may drift into the separation line or into a channel that has already been swept against the mine threat. Therefore, there is also a possibility that a corridor cleared after the agreement may become risky again over time.
The purpose of mine clearance is not to remove all mines, but rather to establish a safe passage corridor. For this purpose, assets such as mine-hunting vessels equipped with side-scan sonar, unmanned underwater vehicles, mine divers and helicopters are used. Since Iran’s naval strategy is based more on laying mines than on clearing them, its mine-clearance capabilities are limited. In this sense, the only dedicated mine-hunting/clearance vessel known to possess modern technology in the Iranian Navy is the domestically built Shahin-class vessel, which entered service in 2021. In addition, although some auxiliary vessels are capable of carrying out limited mine-sweeping missions, there is no capacity comparable to the dedicated mine-hunting fleets of Western navies. Therefore, the capabilities and assets of the U.S. and/or other countries in this field will be needed for mine clearance. Indeed, even before the agreement, some Western countries had already declared intentions[vii] and made deployments[viii] in this regard.
Regarding the process of clearing the mines in the region, it can be said that the duration of clearance depends on the number and type of mines laid. In recent assessments,[ix] some intelligence reports state that at least several dozen advanced mines have been detected in Hormuz, while some sources put this number at 80.[x] Broader estimates suggest that hundreds of mines may have been laid, and that some of these are bottom mines while others are magnetic/acoustic sensor mines, which cannot be easily cleared by conventional sweeping methods. Mine warfare experts speaking to Reuters,[xi] have assessed that a clearance period of 40-50 days may be required for Hormuz to be reopened safely. This period is based on a scenario in which mine-hunting vessels, unmanned underwater vehicles and diver teams from the U.S., the United Kingdom, France and other countries work together.
Considering that the critical point from the perspective of maritime security is not the clearance of all mines, but first and foremost the opening of a safe corridor, the process can be envisaged as follows: reconnaissance with UAVs and maritime patrol aircraft; sonar scanning by mine-hunting vessels; identification through unmanned underwater vehicles; destruction by explosive charges or remotely operated vehicles (ROVs); and finally the declaration of a safe transit corridor. For this reason, although controlled passages by commercial vessels may begin within a few days following the agreement expected to be reached in Switzerland, it is assessed that the complete clearance of the region from mines will take a longer time.
Considering that the main criterion in re-establishing maritime traffic is not the complete removal of mines from the region, but the creation of safe passage corridors, it can be said that controlled passages will be initiated while clearance activities continue, within an acceptable level of risk, in order to improve the situation of ships and seafarers stranded in the region and to reduce disruptions in global energy and trade flows. Open sources indicate that following the signing of the memorandum, a limited number of vessel transits have already taken place.
In conclusion, because of mines and other obstacles following the memorandum that was agreed upon but not followed through, even if the ceasefire that may be described as “fragile” continues, it appears difficult for maritime transportation to return to normal for some time. This situation has once again demonstrated, after the Red Sea Crisis, the dependence of the global supply chain on geopolitical risks, the importance of corridor security and the connection between energy and maritime security.
[i] “Hürmüz Boğazı’ndan ticari gemi geçişlerinde artış”, AA, https://www.aa.com.tr/tr/dunya/hurmuz-bogazindan-ticari-gemi-gecislerinde-artis/3971918, (Date Accessed: 21.06.2026).
[ii] “İsrail saldırılarına karşı Hürmüz kapatılıyor”, 7Deniz, https://www.7deniz.net/israil-saldirilarina-karsi-hurmuz-kapatiliyor, (Date Accessed: 21.06.2026).
[iii] “Iran claims Hormuz closed again as IDF attacks Hezbollah; Vance says Switzerland talks may start Sunday”, Times of Israel, https://www.timesofisrael.com/iran-closes-hormuz-again-as-idf-attacks-hezbollah-upping-pressure-on-us-before-switzerland-talks/, (Date Accessed: 21.06.2026).
[iv] “U.S. Ends Naval Blockade of Iran”, USNI News, https://news.usni.org/2026/06/18/u-s-ends-naval-blockade-of-iran, (Date Accessed: 21.06.2026).
[v] “Mine threat in parts of Hormuz not fully understood, US navy advisory says”, Reuters, https://www.reuters.com/world/mine-threat-parts-hormuz-not-fully-understood-us-navy-advisory-says-2026-04-17/, (Date Accessed: 21.06.2026).
[vi] “How the US could clear mines from the Strait of Hormuz”, Reuters, https://www.reuters.com/business/aerospace-defense/how-us-could-clear-mines-strait-hormuz-2026-04-16/, (Date Accessed: 21.06.2026).
[vii] “UK and France to lead multinational mission to protect Strait of Hormuz, says PM”, Forces News, https://www.forcesnews.com/epic-fury/uk-and-france-lead-multinational-mission-protect-strait-hormuz-prime-minister-says, (Date Accessed: 21.06.2026).
[viii] “Germany Deploys Two Navy Ships for Military Operation in The Strait of Hormuz, Says Defence Minister”, Marine Insight, https://www.marineinsight.com/germany-deploys-two-ships-for-military-operation-in-the-strait-of-hormuz-says-defence-minister/, (Date Accessed: 21.06.2026).
[ix] “Iran’s Hormuz trap: What to know about IRGC’s naval mines deployment”, Gulf News, https://gulfnews.com/world/mena/irans-hormuz-trap-what-to-know-about-irgcs-naval-mines-deployment-1.500484573, (Date Accessed: 21.06.2026).
[x] “Hormuz disruption will continue until 80 mines blocking route are cleared”, Reuters, https://www.theguardian.com/world/2026/jun/19/normal-shipping-will-not-resume-in-strait-of-hormuz-until-mines-cleared, (Date Accessed: 21.06.2026).
[xi] “Scouring the Strait of Hormuz for mines could take weeks”, Reuters, https://www.reuters.com/world/middle-east/scouring-strait-hormuz-mines-could-take-weeks-2026-06-15/, (Date Accessed: 21.06.2026).
