The humanitarian situation in Marib, Yemen, is worsening by the day, with more than 45,000 people fleeing their homes as the Iran-backed Houthi rebels push forward with their offensive to take on Yemen's southern city, several humanitarian agencies said on Wednesday. The battle for <a href="https://www.thenationalnews.com/gulf-news/2021/10/29/yemen-houthi-missile-targets-marib-tribal-leaders-meeting/">Marib</a> began in February and has intensified in recent weeks, with Houthi gains across the gas and oil-producing region, and increased air strikes by the <a href="https://www.thenationalnews.com/tags/saudi-arabia/">Saudi Arabia</a>-led coalition to deter them. "We've not witnessed this much desperation in Marib in the last two years as we have in the last two months," said Christa Rottensteiner, the UN migration agency's Yemen chief representative. The International Organisation for Migration (IOM) said it predicts at least a tenfold increase in migration. "Communities are being repeatedly displaced and arriving at our sites in dire need," Ms Rottensteiner said, adding that up to 40 displaced people were sometimes sharing one small tent. Marib city is home to three million people, including nearly one million who fled other parts of Yemen after the Houthis ousted the government from the capital, Sanaa, in late 2014. "IOM is extremely concerned about the prospect that hundreds of thousands of people might be forced to move again if violence reaches the city, as well as rising civilian casualties and the destruction of civilian infrastructure," said Ms Rottensteiner. The UN Refugee Agency expressed grave concern about the safety and security of civilians in the governorate late on Tuesday, including those displaced. "UNHCR is warning that further escalation of the conflict will only increase the vulnerability of people in Marib, especially those displaced – and is calling for an immediate ceasefire in Yemen," said a statement by the organisation. Some 40,000 people have been forced to flee in Marib since September, according to UNHCR's interagency data. "This represents almost 70 per cent of all displacements in this south-eastern governorate since the beginning of the year. Marib now hosts half of the estimated 120,000 newly displaced countrywide in 2021," said the statement. The seven-year war has created what the UN has called the world's largest humanitarian crisis. The intensification of the war has impacted donations. The IMO said this year's $3.85 billion aid response plan is only 57 per cent funded, and the agency has received only half its requested $170 million. Ahmed Awad bin Mubarak, Yemen's Foreign Minister, said last week that if Marib was to fall into the hands of the rebels, it would "unleash waves of migration". “The fall of <a href="https://www.thenationalnews.com/tags/marib/">Marib</a> won't only lead to a horrific humanitarian situation, it will also mark the end of the political and peace process in Yemen,” he said at an event organised by the International Institute for Strategic Studies. Taking control of Marib would present major gains for the rebels as it is home to oil and gasfields in which international firms including Exxon Mobil and Total SA have interests. Marib’s natural gas bottling plant produces cooking gas for the nation of 29 million people. Its power plant once provided 40 per cent of Yemen’s electricity. “There is a huge need for international actors to do more, people are being evicted from their cities and villages to the centre of Marib,” Mr Mubarak said. Although Marib is considered a safe haven for displaced Yemeni civilians, “the Houthis have not stopped bombing cities and civilians with ballistic missiles”, the foreign minister said. He said the attacks showed the level of weapon supplies from Iran.