RIYADH, Saudi Arabia — The head of Yemen's presidential council on Sunday announced the start of a new military operation to retake all territory held by Iran-backed Houthi fighters.

 

"I announce today the start of military operations to retake the remaining territories of the republic and extend the authority of the state and its institutions across the entire national territory," Rashad Al Alimi said in a statement.

 

Alimi called on "the armed forces, security forces and all military formations to begin carrying out their assigned missions, in accordance with the approved plans, until the country is liberated from the grip of the Houthi terrorist militia".

 

The announcement marks the latest major escalation in the war against the Houthis following a rapid offensive by the Iran-backed group last month that saw them seize large swathes of the Red Sea coastline.

 

The Houthis on Sunday cut a vital supply route linking Taiz with Aden -- the interim capital of the internationally recognised government -- according to four security sources.

 

"We were informed that the Houthis had taken control of the al-Safiya area, where they cut the main road and took control of the police station," a police source in the area told AFP.

 

Three sources with the Yemeni military confirmed Houthi control over the area and supply route, with the group effectively encircling Taiz city.

 

The military sources added that the Houthis had also halted traffic on the main road linking Taiz to Aden, with fighting in the area ongoing.

 

The Houthi surge follows days of heavy fighting in and around Taiz between the group and government forces.

 

The city itself remains under the control of government forces but has long been besieged from the north, east and west by Houthi fighters and remains one of the main fronts in Yemen's civil war.

 

Following several years of relative calm, Yemen's war reignited in July against the backdrop of the widening Middle East war.

 

The country is one of the poorest in the world and remains gripped by a vast humanitarian crisis.

 

Fighting intensified in September as the Houthis launched a lightning offensive that saw them seize Yemen's entire Red Sea coast, including the Bab al-Mandab Strait, a vital shipping lane.