SANAA - Yemen’s Iran-aligned Houthis will impose a maritime blockade on Saudi Arabia, they said on July 20, further throttling a global energy market already greatly restricted by Iran’s closure of the Strait of Hormuz.

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It is not clear how the Houthis would carry out a maritime blockade of Saudi Arabia, its northern neighbour along the Red Sea coast, or whether it would include a return to attacks on shipping.

Yemen sits on the Bab el-Mandeb strait – the southern gateway to the Red Sea – and closing that would open up a new front in the energy crisis and Iran’s overarching conflict with the US.

With Hormuz already disrupted, the Red Sea has become a critical alternative outlet for Gulf oil and other products. A serious disruption would mean both of the Middle East’s major oil export routes are shut simultaneously.

Iran’s partial blockade of the Strait of Hormuz after Israel and the US attacked it on Feb 28 disrupted most oil and other exports from the Gulf, raising prices and delivering a global energy shock.

Saudi Arabia responded by diverting more than 70 per cent of its normal daily crude exports to the Red Sea port of Yanbu.

Ships from Yanbu bound for Europe go north through the Suez Canal. Those heading to Asia go south through Bab el-Mandeb.

Shipments from Yanbu averaged 4 million barrels per d...