Iran’s parliament has voted to close the Strait of Hormuz, the vital shipping channel through which around 20% of the world’s daily oil flows. The move, which could block $1 billion in oil shipments per day, is likely to send oil prices soaring. It will come into effect pending a final decision by Iran’s Supreme Council. The Supreme Council’s decision must be made by June 22 evening, according to Iran’s state-run Press TV. Iran’s major escalation in response to US strikes on its nuclear facilities “will be done whenever necessary,” Email Kosari, Commander in the Revolutionary Guards, said. The strait connecting the Gulf of Oman with the Persian Gulf is one of the world’s most critical chokepoints — just 20 miles wide at its narrowest point. Shipping lanes in the strait — the area that is deep enough for ships to pass — are even narrower at less than two miles wide in each direction, making them much more vulnerable to attacks and threats of closure. The channel is shallow, making it a particular target for underwater mining, while the narrowness of the strait makes passing vessels vulnerable to attack from shore-based missiles or interception by patrol boats or helicopters. Iran has no legal authority to block sea traffic through Hormuz, and any attempts by its navy to bar entry to the strait would likely be met by a strong response. Ships with the US Fifth Fleet, along with other Western navies, are patrolling the area at all times. It is bordered by Iran to the north and Oman and the United Arab Emirates to the south. The bulk of all oil exported by the regional petro giants, Iran, Iraq, Kuwait, Qatar, Saudi Arabia and the UAE, all travel through this narrow waterway. Asia is likely to bear the brunt most from any closures to the waterway, with China, India, Japan and South Korea all getting most of their oil imports through the strait. China, the world’s biggest buyer of Iranian oil and a critical partner that has previously used its veto power at the UN Security Council to block sanctions or resolutions against Tehran, would be particularly affected by any closure. The move would also hit Iran’s own economy. Iran last disrupted traffic in the Persian Gulf in April last year when it seized an Israel-linked container ship near the Strait of Hormuz, accusing the MSC Aries of violating maritime regulations. In April 2023, Iran seized a US-bound tanker, claiming the ship had struck another vessel. And in May 2022, two Greek tankers were held for six months in what was widely seen as retaliation to the confiscation of Iranian oil on a different ship by Greek and US authorities. In previous years, the Houthi militia in Yemen was able to successfully disrupt traffic through the Bab el-Mandeb Strait leading into the Red Sea on the other side of the Arabian Peninsula. Using the firing of missiles and drones, the Houthis were able to cut ship traffic through the Red Sea and the Gulf of Aden some 70% in June compared with the average levels in 2022 and 2023, according to Clarkson Research Services Ltd, a unit of the world’s largest shipbroker. Vessel operators have been forced instead to reroute traffic around the southern tip of Africa instead of using the Suez Canal, making journeys for ships traveling between Europe and Asia vastly more expensive and much longer. 📸: NurPhoto via Getty Images; Gallo Images via Getty Images - @nypost