The UN’s hopes of negotiating a ceasefire with Houthi rebels in the vital port of Hodeidah in Yemen appear to have been dashed after the Saudi-led coalition backing the Yemeni government said it would only accept the rebels’ unconditional withdrawal from the area.

The UN special envoy for Yemen, Martin Griffiths, has been in the country seeking a deal whereby the port, currently under Houthi control, is handed over to the UN and its relief agencies. The port is the distribution point for up to 80% of the food, water and commercial fuel vital to the lives of more than 8 million Yemenis in severe need. The UN and aid agencies fear a prolonged fight will endanger the aid supplies.

But the United Arab Emirates, the key military supporters of the UN-backed government, has insisted it will not accept anything but an unconditional withdrawal.

Timeline Yemen's civil war Show Hide 2011 An Arab Spring-inspired uprising forces Yemen’s authoritarian president, Ali Abdullah Saleh, to agree to leave office. 2012 Abdrabbuh Mansur Hadi, previously Saleh’s deputy, takes over as president following an election. He was the only candidate. He struggles to unite the country’s divided political landscape, cope with food insecurity and al-Qaida threats.

2014 Houthi rebels (who belong to the Zaydi sect of Shia Islam) make advances and begin capturing the north of the country, an area they have historically controlled. In September they enter the capital, Sana’a. Hadi flees to Aden.

2015 A renewed rebel offensive forces Hadi to flee to Saudi Arabia, which views the Houthis as an Iranian proxy force. It begins bombing what it says are “military targets” associated with the Houthis and forces loyal to Hadi’s predecessor, Saleh. The Saudi air campaign receives backing from a coalition of Sunni Arab states, as well as logistical support from the US, UK and France.

June 2016 The Saudi-led coalition is included on a UN blacklist of states and groups that violate children’s rights in conflict, reporting it is responsible for 60% of child deaths and injuries. After Riyadh protests, the UN removes it from the list. Human Rights Watch warns of “political manipulation”. At least 6,200 people have been killed, 2.8 million displaced.

October 2016 An airstrike by the Saudi coalition hits a funeral in Sana’a, killing 140. The UN announces a 72-hour ceasefire, which is allegedly broken by both sides.

2017 Devastated by two years of fighting, Yemen is described by the UN as the world’s worst humanitarian crisis. Millions facing famine and the threat of cholera.

November 2017 Saudi Arabia imposes a blockade on Yemen’s ports, following the firing of a missile at Riyadh from rebel-held territory in Yemen. Medicines, vaccines and food are prevented from entering the country. The heads of the World Food Programme, Unicef and the World Health Organisation warn “untold thousands of innocent victims, among them many children, will die”.

Rebecca Ratcliffe

The Houthis are extremely unlikely to agree to this, since it would amount to surrender of the area with no guarantees on the future status of Yemen.

“There can be no conditions in any offers to withdraw,” the UAE’s foreign minister, Anwar Gargash, told a press briefing in Dubai.

“If the rebels wanted to set conditions, they should have thought of that a year ago … Now is not the time to negotiate.”

Gargash’s remarks reflect his military planners’ confidence that the estimated 3,000 Houthi troops in the area can be defeated without damage to the port infrastructure. He said: “Our approach is one of gradual, calibrated and methodical pressure designed for unconditional withdrawal of Houthis. Our earlier efforts to ensure Hodeidah as a humanitarian and commercial port failed. It became quickly clear that the Houthis were buying time. Their financial and strategic interest was to prolong the war. We will not allow this war to last for another two to three years.”

He added: “It is time for a political process. The Houthis need to be part of that process – but you can’t be 3% of the population, yet claim through the barrel of a gun to own 50% of the country.”

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UAE sources may also fear that a ceasefire would give the Houthis a chance to regroup and acquire extra arms, or to try to rebuild international diplomatic support against the attack. Fighting around the Hodeidah airport continueds, but the massive air superiority of the Saudi coalition appears to be helping Yemeni government ground forces to make progress.

The UAE sources said the coalition had captured the southern part of the airport, but has not yet secured the perimeter due to an unwillingness to fire on Houthi forces hiding among civilians in a village to the west of the airport.

On Sunday the UN’s humanitarian coordinator for Yemen, Lise Grande, said talks on a transfer of the port to UN control were at an advanced stage. Griffiths is expected to brief the security council on his talks later on Monday, and will set out the continuing points of difference between the two sides.

Gargash said the Saudi and UAE-led offensive aimed “to help the UN envoy in his last chance to convince the Houthis to withdraw unconditionally from the city and avoid any confrontation”. He pointed out the road for Houthis to leave Hodeidah and head for the capital Sana’a had been kept open.

The head of the Houthis’ unofficial government, Abdulaziz bin Habtoor, accused Saudi-led forces of “escalating their attacks on the western coast when they felt there were serious moves towards a solution”.

The Saudi alliance imposed a near-total blockade on Hodeidah port earlier this year, alleging Iran was using it as a major conduit for illicit arms deliveries to the Houthis.

Gargash said on Monday that his country and its allies aimed to “avoid civilian casualties”, adding that the operation was “going very well”.