The insurance cost of shipping goods through the southern Red Sea doubled for some companies on Thursday, after Yemen’s Iran-aligned Houthis attacked at least one tanker overnight, sources said.

The Houthis said their forces had carried out missile and drone strikes on Saudi oil tankers, the Encelia and the Layla. This worsened the turmoil for shipping in the region, with the Strait of Hormuz essentially shut down.

Maritime security sources confirmed the strike on the Encelia, off the coast of the southern Saudi port of Jizan, close to Yemen’s border.

Reuters could not immediately confirm the attack on the Layla, but U.S. President Donald Trump mentioned two attacks on Saudi tankers.

On Monday, the Houthis declared a naval blockade against Saudi Arabia, opening a potential new front against the U.S. in its war with Iran.

On Thursday, the sources said, indicative war risk premiums for voyages through the southern Red Sea rose to over 1% of the value of a ship from around ⁠0.75% on Tuesday and 0.3% last week before the Houthi announcement, according to the sources, who declined to be identified due to the sensitivity of the matter.

Rates for some shipping companies calling at Saudi ports and also Saudi-linked ships were quoted as high as 3% for voyages from southern Saudi ports in the Red Sea such as Jizan and Al Shuqaiq, which would take them closer to Yemeni territory and for transits through the Bab el-Mandeb gateway further south that leads into the Gulf of Aden, the sources added.

Even small changes to war insurance add hundreds of thousands of dollars in extra costs for a seven-day voyage.

Rates for other Saudi Red Sea ports, such as Jeddah and Yanbu, which are further north up the coast and closer to the Suez Canal, were quoted around 0.1% reflecting a lower risk profile for the moment, sources said.

Two Chinese supertankers that loaded Saudi oil at Yanbu this week sailed through the Bab el-Mandeb on Wednesday. It was unclear what insurance costs were paid.

Red Sea traffic has not fully recovered since Houthi attacks off Yemen’s coast began in November 2023, with the group citing solidarity with Palestinians in the Gaza war.

The group’s attacks on merchant ships only ended with the Gaza ceasefire last October.

Successful passage of a China-owned tanker through the Bab el-Mandeb suggested “the blockade will be targeted at vessels linked to Saudi and Western interests, as was the case during the 2023-25 Houthi Red Sea anti-shipping campaign,” said Hamish Kinnear, principal Middle East and North Africa analyst at risk intelligence company Verisk Maplecroft.

“Shipping firms now have to contend with heightened risks through two trade chokepoints, with several vessels already forced to re-route in response to Houthi threats.”

(Reporting by Jonathan Saul and Michael Jones with the Insurer; editing by David Gregorio)

Photograph: The sun rises behind a tanker anchored in the Strait of Hormuz off the coast of Qeshm Island, Iran, on Saturday, April 18, 2026. (AP Photo/Asghar Besharati)

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