Commercial ships remain cautious about transiting the strait as tensions escalate between the U.S. and Iran again.

Commercial ships came under fire and threats from Iran's military as they tried to cross the Strait of Hormuz on Saturday, security monitors said, as Iran closed the crucial trade route again

The day after Iran declared the vital waterway open, it reversed course, injecting new peril into navigation there.

Two IRGC gunboats approached a tanker about 20 nautical miles northeast of the Gulf country around 1 p.m. local time — and opened fire unprovoked, the tanker’s master reported.

Analysts warn shipping risks through the conduit are at their highest level yet after this weekend's vessel strike and U.S. seizure of an Iranian-linked ship.

The vessels were forced to dock in ports throughout the Persian Gulf since the conflict broke out on Feb. 28

Ship-tracking data shows 279 ships have passed through the strait and 22 have been attacked since the war on Iran began.

Crude oil prices surged Sunday, as the U.S. and Iran teetered on the brink of a renewed war after attacks on commercial ships in the Strait of Hormuz.

MSC Cruises, TUI Cruises and Celestyal Cruises all reported that their ships had safely transited the Strait of Hormuz.

Merchant vessels attempting to cross the strait on Saturday received radio messages from Iran's navy telling them they were not allowed to pass.

WASHINGTON/ISLAMABAD, April 19 - Iran's top negotiator said recent talks with the U.S. had made progress but gaps remained over nuclear issues