Brent crude tops $106 a barrel as markets see no end in sight to the halt of traffic through the critical waterway.
Oil prices are continuing to rise as markets see no end in sight to the effective closure of the Strait of Hormuz.
Brent crude, the most important benchmark for global prices, rose as much as 3 percent on Sunday to top $106 a barrel, before easing slightly early on Monday.
Brent stood at $104.63 a barrel as of 04:30 GMT, up nearly 1.5 percent.
The latest rise came after US President Donald Trump called on other countries to help Washington reopen the Strait, which usually transports about one-fifth of the global oil supply.
Trump’s proposal has received a muted response so far, with none of the countries he appealed to by name – including China, Japan, France and the UK – publicly committing to deploying their navies to secure the strait.
In an interview with The Financial Times on Sunday, Trump said that NATO would face a “very bad” future if his proposal received “no response, or if it’s a negative response”.
Japan and Australia on Monday both said they had no plans to send ships to the critical waterway.
Iran has brought shipping in the strait to a standstill in retaliation for the US and Israel’s strikes on the country, resulting in what the International Energy Agency has called the largest disruption to global energy supplies in history.
Global oil prices have risen more than 40 percent since the start of the war, pushing up fuel prices and heightening fears of a slowdown in the global economy.
According to the United Kingdom Maritime Trade Operations (UKMTO) centre, no more than five ships have passed through the strait each day since the start of the war, compared with a historical average of 138 daily transits.
At least 16 commercial vessels have been attacked in the region since the war began on February 28, according to the UKMTO.
Trump has repeatedly said he is willing to deploy the US Navy to escort commercial shipping through the strait, which is bordered by Iran, Oman and the United Arab Emirates, if necessary.
Trump administration officials have said that warships will not be deployed to the waterway until Tehran’s military capacity has been further degraded, but that they expect such operations to begin soon.