Iran has largely blocked shipping through the strait since the outbreak of war with the United States and Israel on February 28.

In peacetime, the route accounts for roughly a fifth of global oil and liquefied natural gas shipments, along with other key commodities.

"Following a decision by the Islamic republic, a number of Chinese vessels have been allowed to pass through the Strait of Hormuz under Iranian-managed transit protocols," the Tasnim news agency said.

It added that the passage, which was requested by Beijing, began on Wednesday evening after "an understanding on Iranian management protocols".

Fars news agency also carried a similar report, while Iranian state television said "more than 30 ships" had been allowed to pass, although it was not clear if they were all Chinese.

Iran's grip over the waterway has rattled global markets and given Tehran significant leverage, while the United States has imposed its own naval blockade on Iranian ports.

The passage of ships comes with US President Donald Trump visiting China, where he met counterpart Xi Jinping on Thursday for talks that included the Iran war.