A Saudi-led coalition says it has attacked 324 "high-value targets" in an operation involving 100 fighter jets against the Iran-backed Houthis in Yemen.

The intense air campaign was in support of Yemeni forces of the internationally recognised government which have begun a major offensive against the rebels.

Yemen's ‌Houthi-run maritime coordination body ‌issued a warning ​on Monday for airlines ​flying in ‌Saudi airspace, Houthi-affiliated media ​reported.

The government forces reportedly seized key positions on the Bab el-Mandeb Strait in the Red Sea on Monday as they fought to reverse last month's advances by the Houthis and drive them from the vital waterway where 12% of global trade passes.

With Gulf energy exports ​already restricted by Iran's partial closure of the Strait of Hormuz, the fighting in Yemen has threatened another major oil export route, ⁠pushing up global prices.

Saudi military spokesperson, Major General Turki al Malki, said the coalition has secured "air protection" of the strategic strait and destroyed hundreds of Houthi targets as part of the ongoing campaign.

Also, the Yemeni government said it had launched attacks on several fronts including in the province of Sanaa, the Yemeni capital.

Government forces have taken large parts of ​Dhubab district, which overlooks Bab el-Mandeb, and are asserting full control over the area with air support from the Saudi-led coalition, military and government sources told Reuters.

Houthi-aligned media earlier denied government forces had made advances ​in the area, calling such claims "completely untrue".

The Houthis have also fired missiles and drones at cities and infrastructure in Saudi Arabia, which arms and trains Yemeni government forces.

The Saudis have sought logistical help from allies to push back the Houthis, restore free traffic in the Red Sea, and end the group's attacks on its territory.

Yemen's civil war started in 2014 when the Houthis seized ​the capital Sanaa, leading to a Saudi-led coalition carrying out an air campaign the following year to restore ​the government and oust the Tehran-backed group.

But the fighting quickly ground to a stalemate, leading to a major humanitarian crisis until a ceasefire was agreed in 2022 ‌that held for four years until this summer, when there was an escalation between both sides.

Where has the latest fighting taken place?

Late on Sunday, the Houthis reportedly advanced to sections of the ‌mountain road to the third-largest city of Taiz, surrounding government forces.

Also on Sunday, Houthis said they captured more territory in the southwestern part of the country - seizing the key town of Turbah in a setback to the Saudi-backed forces.

Turbah is located on a main road linking the provincial capital of Taiz with the port city of Aden, which serves as an interim base of Yemen's government.

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The Houthis made a swift push on the country's western coast on the Red Sea in early September.

They captured the strategic city of Mokha and several Red Sea islands, gains that allowed them to control the Yemeni side of the Bab el-Mandeb Strait.

In a televised speech on Sunday, Rashad al Alimi, head of the ruling Presidential Leadership Council, said the operations were aiming at "recovering the remaining territories" controlled by the Houthis.

He called for the international community to provide support to his government, which in turn led Saudi military spokesperson, Major General Turki al Malki, to pledge "full operational support" to the Yemeni government forces until the Houthis are "eliminated".