Diplomatic sources said veto-holding Russia, a key ally of Iran, had warned on Wednesday it was prepared to block the UN Security Council resolution.

US Ambassador Mike Waltz -- speaking Thursday alongside counterparts from Bahrain, Saudi Arabia, the United Arab Emirates, Qatar and Kuwait -- argued the issue had global consequences.

"We believe in some basic fundamental principles, namely the freedom of navigation for the entire world's economies," Waltz said. "That's what's at stake here, nothing less than a cornerstone of worldwide stability and commerce."

A draft resolution from the United States and Bahrain, seen by AFP, demands that Iran halt its attacks and threats against commercial vessels in the Strait of Hormuz.

It also orders Iran to not charge tolls on the passage, to specify where it has placed mines, and allow for the creation of a humanitarian corridor for shipments of fertilizer, amid fears of global food shortages.

A fifth of the world's oil supplies and a third of the global fertilizer shippments normally pass through the Strait of Hormuz, but shipping has been largely cut off since the war broke out on February 28 with US and Israeli attacks on Iran.

Iran's UN ambassador blasted the draft resolution as a "flawed, politically motivated" text that would not resolve the crisis.

Passing the resolution would "establish a dangerous precedent for legitimizing unilateral coercive measures and unlawful actions by the United States against the sovereignty and sovereign rights of coastal states," said Amir Saeid Iravani.

In mid-March the council passed a strongly worded resolution urging Iran to stop attacking its Gulf neighbors and condemning its chokehold on the Strait of Hormuz.

Russia and China abstained in that vote. But in early April they vetoed a text urging countries to coordinate their efforts in a "defensive" way to ensure free navigation through the strait.