Reinforcements rolled into Yemen's Hudaida Thursday as the army and its regional allies set their sights on the city's port held by rebels who have vowed to fight to the end.
Military sources said the army, backed by troops from the United Arab Emirates (UAE), had been sending backup troops to the area ahead of a major offensive to close in on the Red Sea port.
"Our preparations are in their final stages for the advance on the port," a military source told AFP, requesting anonymity.
On Tuesday, Yemeni government forces backed by a Saudi-led military coalition captured Al-Hudaida’s international airport following clashes with Houthi rebels.
Yemen’s internationally-recognized government (currently based in the port city of Aden) and its allies accuse the Houthis of using Al-Hudaida to smuggle weapons into the country from Iran.
The Iran-allied Houthi rebels have refused to cede control of Hudaida port, the entry point of three quarters of imports to impoverished Yemen.
Iran on Thursday dispatched two warships to the Gulf of Aden, where for the last week fighting has raged between the Yemeni army and Houthi rebels over Yemen’s Al-Hudaida province.
According to Iran's semi-official Tasnim News Agency, Iran has sent both a helicopter-carrier and a naval destroyer to the region.
A highly strategic waterway, the Gulf of Aden links the Indian Ocean to the Red Sea.
The Houthis have controlled the port since 2014, when they drove the government out of the capital and seized much of northern Yemen and a string of Red Sea ports.
On June 13, Yemen's army and its allies launched their offensive to clear Hudaida of the rebels, raising UN concerns for vital aid shipments and food imports through the city's docks.
The pro-government forces announced the capture of the Hudaida airport on Wednesday morning.
The airport had been disused but it housed a major rebel base just inland from the coastal road into the city.
Rebel leader Abdulmalik al Houthi on Wednesday night called for reinforcements to repel the advance of the UAE-backed government forces, after ongoing fighting left nearly 350 people dead in one week.
Hudaida's residents are now bracing for what they fear will be devastating street fighting, as tanks and buses carrying uniformed troops roll through the empty streets of the once-bustling city.
The Hudaida offensive, dubbed Operation Golden Victory, is the most intense battlefront in the already-brutal Yemen war which has left millions displaced.
Impoverished Yemen has remained wracked by violence since 2014, when Shia Houthi rebels overran much of the country, including capital Sanaa.
The conflict escalated in 2015 when Saudi Arabia and its Sunni-Arab allies -- who accuse the Houthis of serving as proxies for Shia Iran -- launched a massive air campaign in Yemen aimed at rolling back Houthi gains.
The following year, UN-sponsored peace talks in Kuwait failed to end the destructive conflict.
The violence has devastated Yemen’s infrastructure, including water and sanitation systems, prompting the UN to describe the situation as “one of the worst humanitarian disasters of modern times”.
The Yemen conflict has since killed nearly 10,000 people, most of them civilians, since 2015, when Saudi Arabia and its allies joined the government's fight against the Houthis.