Iran's Military Blocks Strait of Hormuz Amid Tensions

WHO:

CNN - Matt Smith, lead oil analyst at Kpler

CNN - Jakob Larsen, chief safety and security officer at the Baltic and International Maritime Council (BIMCO)

CNN - Ben Bailey, director of programme for Mission to Seafarers

CNN - Tom Kloza, independent oil analyst and adviser to Gulf Oil

Newsweek - U.S. Vice President JD Vance

WHAT:

CNN - The number of tankers that sailed through the Strait of Hormuz on a Thursday was reported as 25, but fell back to single digits the following day after the first round of talks between Iran and the United States was canceled.

CNN - Experts agree it will take months for ship traffic and oil flows to return to normal despite the signing of an agreement to end the fighting.

CNN - An estimated 20,000 crew members are still stuck on ships in the Persian Gulf.

CNN - Maritime insurers have yet to declare they will cover damage from war risk, which was withdrawn in the early days of the war.

CNN - Ships may require maintenance, such as scraping barnacles, before they can set sail after being anchored for months.

CNN - The number of tankers that sailed through the Strait of Hormuz on a Thursday was reported as 25, the highest since mid-April, but fell back to single digits the following day after talks between Iran and the United States were canceled.

CNN - Experts agree it will take months for ship traffic and oil flows to return to normal despite the signing of an agreement to end the fighting.

CNN - Approximately 120 tankers filled with oil are expected to take weeks to exit the Gulf, and it will take longer for the 100 empty tankers to fill up and leave.

CNN - Nearly 500 ships, including 220 oil tankers, have been trapped in the Persian Gulf since the start of the war.

CNN - Maritime insurers have yet to declare they will cover damage from war risk, which was withdrawn in the early days of the war.

CNN - The central part of the Strait is mined and unnavigable, with only inshore traffic zones reportedly free of mines.

CNN - Ships may require maintenance, such as scraping barnacles, before they can set sail after being anchored for months.

CNN - The number of tankers that sailed through the Strait of Hormuz on a Thursday was reported as 25, the highest since mid-April.

CNN - The number of tankers fell back to single digits the following day after talks between Iran and the United States were canceled.

CNN - Approximately 120 tankers filled with oil are expected to take weeks to exit the Gulf, and it will take longer for the 100 empty tankers to fill up and leave.

CNN - An estimated 20,000 crew members are still stuck on ships in the Persian Gulf.

CNN - Maritime insurers have yet to declare they will cover damage from war risk, which was withdrawn in the early days of the war.

CNN - Ship operators had pulled back on sailings through the Strait of Hormuz even before Iran announced it was closed again.

CNN - The number of tankers fell back to single digits on Friday after the first round of talks between Iran and the United States was canceled.

CNN - Experts agree it will take months for ship traffic and oil flows to return to normal despite the signing of an agreement to end the fighting.

CNN - Approximately 100 empty tankers are expected to take longer to fill up and leave the Gulf.

CNN - Maritime insurers have yet to restore coverage for war risk, which was withdrawn in the early days of the war.

CNN - Ships may require maintenance, such as scraping barnacles, before they can set sail after being anchored for months.

CNN - Iran announced that the Strait of Hormuz was closed.

CNN - Twenty-five ships traveled through the Strait of Hormuz on a Thursday, the highest since mid-April.

CNN - The number of tankers fell to single digits the following day after talks between Iran and the United States were canceled.

CNN - Nearly 500 ships, including 220 oil tankers, have been trapped in the Persian Gulf since the start of the war.

CNN - Approximately 120 tankers filled with oil are expected to take weeks to exit the Gulf.

CNN - An estimated 20,000 crew members are still stuck on ships in the Persian Gulf.

Newsweek - The Iranian Army declared the Strait of Hormuz "closed" over a breach of a memorandum of understanding (MOU).

WHERE:

CNN - The Strait of Hormuz, a critical channel between Iran and Oman.

CNN - The Persian Gulf.

WHEN:

CNN - The last significant vessel traffic was reported on a Thursday, with the highest number since mid-April.

WHY:

CNN - Iran stated that Israel's continued attacks in Lebanon are a breach of Tehran's agreement with the US to end the war.

CNN - The security situation for the shipping industry remains volatile despite the ceasefire agreement.

CNN - Ship operators are hesitant to sail due to safety concerns and the volatile security situation in the region.

CNN - Maritime insurers have not restored coverage for war risk, contributing to the reluctance of ship owners to navigate the area.

HOW:

Bloomberg Markets - Ships can consider transiting the Strait of Hormuz along the southern route, day or night, with their transponder signals on, according to a key naval information group.

CNN - Practical issues include whether ships are still seaworthy after being anchored for more than three months and if they have the necessary fuel and supplies to sail.

CNN - The central part of the Strait is mined and unnavigable, with only inshore traffic zones reportedly free of mines.

CNN - Ships may require maintenance, such as scraping barnacles, before they can set sail after being anchored for months.

(UPDATED June 21, 2026 04:16 UTC)

Tensions in the Strait of Hormuz have led to a significant drop in tanker traffic, with only a handful of vessels sailing through after the cancellation of talks between Iran and the United States. Experts predict it will take months for normal ship traffic and oil flows to resume, while around 20,000 crew members remain stranded on ships in the Persian Gulf, facing potential maintenance issues before they can set sail. Additionally, maritime insurers have not yet reinstated coverage for war risk damage, which was withdrawn at the onset of the conflict, leaving many vessels in a precarious situation.

(UPDATED June 20, 2026 23:20 UTC)

The number of tankers that sailed through the Strait of Hormuz recently peaked at 25, the highest since mid-April, but dropped back to single digits after talks between Iran and the United States were canceled. Experts predict that it will take months for ship traffic and oil flows to return to normal, with approximately 120 tankers expected to take weeks to exit the Gulf, while 100 empty tankers will require even more time to fill up and leave. Meanwhile, the central part of the Strait remains mined and unnavigable, although ships can transit along the southern route with their transponder signals on, as they prepare for departure after being anchored for months.

(UPDATED June 20, 2026 21:18 UTC)

The number of tankers that sailed through the Strait of Hormuz reached 25 on a Thursday, marking the highest count since mid-April, but this number plummeted to single digits the following day after talks between Iran and the United States were canceled. Approximately 120 oil-filled tankers are expected to take weeks to exit the Gulf, while an additional 100 empty tankers will take even longer to fill up and depart, leaving around 20,000 crew members stranded on ships in the Persian Gulf. Iran has claimed that Israel's ongoing attacks in Lebanon violate Tehran's agreement with the U.S. to end the war, contributing to the current maritime tensions.

(UPDATED June 20, 2026 19:21 UTC)

Shipping activity through the Strait of Hormuz has significantly decreased, with operators pulling back on sailings even before Iran announced its closure again. Following the cancellation of the first round of talks between Iran and the United States, the number of tankers has dropped to single digits, and experts predict it will take months for traffic and oil flows to normalize. Additionally, with maritime insurers yet to restore war risk coverage and many ships needing maintenance after being anchored for months, the situation for the shipping industry remains precarious despite the recent ceasefire agreement.

(UPDATED June 20, 2026 17:23 UTC)

Iran has announced that the Strait of Hormuz is closed, following a breach of a memorandum of understanding, which has left nearly 500 ships, including 220 oil tankers, trapped in the Persian Gulf. The closure comes as ship operators remain hesitant to navigate the area due to safety concerns and the volatile security situation, with maritime insurers yet to restore coverage for war risk. As a result, approximately 120 tankers filled with oil are expected to take weeks to exit the Gulf, and many ships may require maintenance before they can set sail after being anchored for months.