LONDON (AFP)

Commercial ships came under 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 following a brief reopening.

Iran reversed its pledge to reopen the strait to commercial traffic during a ceasefire in the war in protest at an ongoing US counter-blockade of the route, a crucial passage for commodity shipments.

A handful of oil and gas tankers crossed the strait early on Saturday during the brief reopening, tracking data showed, but others retreated and tracking platforms showed hardly any vessels crossing the waterway by the late afternoon.

Ships dash through

Around a fifth of the world's oil and liquefied natural gas passes through the strait in peacetime.

During the reopening, at least eight oil and gas tankers crossed the strait early Saturday after the Iranian announcement on Friday afternoon, data from tracking firm Kpler indicated.

Tracking platform MarineTraffic showed several other crude oil tankers approached the strait but turned back near Larak Island, a checkpoint for vessels seeking to exit the Gulf under the Iranian blockade of the passage.

Iran tightens control

Iran's central military command on Saturday appeared to reverse the decision to reopen the route, saying it would resume "strict management" of the strait because of the continued US naval counter-blockade.

Iran's closure of the strait has trapped hundreds of ships in the Gulf and driven up the price of oil and the costs of shipping goods, with captains avoiding the region for fear of attacks or mines.