Ships Test Strait of Hormuz After Reopening, Seek Security Guarantees

18 April 2026

A group of ships made an unsuccessful attempt to exit the Gulf on Friday night, tracking data showed, and shipping companies cautiously welcomed Iran’s announcement that the Strait of Hormuz is open.

Iranian authorities said on Friday that the main navigable route was open to all commercial traffic during a 10-day ceasefire in Lebanon, causing a drop in oil prices and other commodities and lifting stock markets.

About 20 vessels began to sail toward the Strait of Hormuz on Friday night, but soon stopped — some even turning back — according to MarineTraffic data. It was the largest group of ships attempting the passage since Iran effectively closed the strait in response to Israeli and American attacks that began on February 28.

It was not immediately clear why the ships stopped. The group included three container ships operated by the French shipping group CMA CGM, which declined to comment.

As of 6 p.m. Brasília time, most of the group’s ships had returned, but tracking data showed other vessels, mainly tankers, heading toward the strait.

Maritime transport companies greeted Iran’s announcement with caution, saying they needed clarifications before resuming transit, particularly with regard to safety risks, such as the presence of naval mines.

All commercial ships, including those under the American flag, may pass through the strait, but transit plans must be coordinated with Iran’s Islamic Revolutionary Guard Corps, said a senior Iranian official to Reuters.

Ships are restricted to routes deemed safe by Iran, while military vessels must remain barred, the official said.

‘We are currently assessing the recent announcement related to the reopening of the Strait of Hormuz, in terms of its compliance with freedom of navigation for all merchant ships and safe passage’, said Arsenio Dominguez, Secretary-General of the United Nations’ maritime agency, the International Maritime Organization.

James Whitmore

James Whitmore

I am a financial journalist specialising in global markets and long-term investment strategies, with a background in economics and corporate finance. My work focuses on translating complex financial data into clear, actionable insights for private investors and professionals. At Wealth Adviser, I contribute in-depth analysis on equities, macroeconomic trends, and portfolio construction.