The Houthis are trying to manufacture their own ballistic missiles, reportedly using components delivered by a Chinese company, according to information by Conflict Armament Research seen by the Wall Street Journal.
The Iran-backed group has bought a range of parts from a Chinese supplier and is attempting to locally produce Tehran's Kheibar Shekan missile, a cheap, precision-guided projectile that can evade air defences.
The Conflict Armament Research report says the missile would have a range of around 1,200 miles, enabling the group to launch strikes across the Gulf, Israel, Jordan and most of Egypt.
This is one of the first indications that the group is pursuing an advanced indigenous weapons programme independently of Iran.
The report was based on information given by Yemeni authorities in July after officials intercepted two shipments last year.
China has also emerged as one of Iran's biggest suppliers of dual-use components during its war with the US and Israel.
Customs data has shown hundreds of shipments have been delivered to Iran's defence ministry in recent months, providing it a vital lifeline to maintain military production during the war.
Advance on Taiz
The Houthis continued to advance towards Taiz on Tuesday, capturing the western entrance to the city.
The country's third-largest city is a major stronghold of the Saudi-backed Yemeni government's and has been a battleground since the long-running conflict was reignited in September amid the US-Iran war.
A Houthi offensive last week saw the group encircle the city, severing its last remaining supply lines.
Military sources told Reuters that clashes were ongoing in al-Dabab, 10 km from Taiz, and on Sabr Mountain, which overlooks the southern edge of the city.
Yemeni warplanes targeted Houthi forces in Dabab and Misrakh south of the city, government forces said in a statement on Tuesday.
Civilian casualties in the city are also mounting as the Houthis advance closer to the city. Yemen's internationally recognised government said Houthi shelling and drone attacks on Monday were responsible for the deaths of at least six people, including a child, and the wounding of another 17 in the city.
It accused the group of shelling residential areas of the city, damaging seven buildings.
Meanwhile, Houthi-affiliated media said one woman was killed and four others injured in an airstrike by the Saudi-led coalition outside the city.
Fears for civilians amid siege
Yemeni civilians in Taiz are facing a "devastating" humanitarian crisis as Houthi forces step up their attacks on the blockaded city, the UN has warned.
"We're alarmed by the intense hostilities across multiple front lines, particularly in Taiz, which is having devastating humanitarian consequences for civilians," UN spokesperson Stephane Dujarric said at a press briefing on Tuesday.
He warned that the blockade was beginning to cause shortages and drive up the prices of goods. Wheat and flour supplies could run out in less than three weeks, he said.
Dwindling fuel supplies are beginning to affect the water supply, risking water shortages for the estimated one million people who live in the city.
The World Health Organisation on Tuesday warned that the war is causing a resurgence in cholera. One quarter of the 8000 cases declared this year have occurred in the past four weeks alone, it said.
The resumption of the conflict last month has triggered a renewed humanitarian crisis across much of the country, displacing hundreds of thousands of people and putting millions at risk of famine.
