The UN's special envoy to Yemen Martin Griffiths called for a ceasefire during a visit to Marib province, the last northern stronghold of the government, on Saturday<em>.</em> "Griffiths arrived in an urgent visit to the city this morning," a source told <em>The National</em>, adding that he met the governor of Marib, Sheikh Sultan Al Arada, and other government officials as well as tribal leaders and representatives of displaced people. During his one-day visit Mr Griffiths called for an immediate, unconditional ceasefire in Yemen in comments to journalists. He warned a large-scale conflict may erupt in the oil-rich province of Marib if the warring parties did not de-escalate immediately. “We will either silence the guns and resume the political process, or we will slip back into large-scale conflict and suffering that you have already seen here in Marib,” he said, adding that Yemen is at a critical juncture. “I'm reiterating my call for an immediate and unconditional freeze, and the start of a comprehensive, inclusive and accountable de-escalation process. The initial positive responses I had from the parties must turn into immediate action on the ground,” he said. Mr Griffiths' visit came days after bloody clashes between the Iran-backed Houthi rebels and pro-government forces in Jawf province north of Marib. The Houthi offensive caused about 25,000 people to flee, according to Najeeb Al Sadi, an official tasked with dealing with civilian displacement. “Hundreds of families fled to the city of Marib and other families were stranded in the desert between the provinces of Jawf and Marib while looking for safety,” Mr Al Sadi said. Fares Saeed, a Yemeni journalist, told <em>The National</em> that Mr Griffiths' visit to the city would not change the dynamics on the ground. “Mr Griffiths visited Marib trying to convince the government to decline any military plans to recapture Al Jawf province, not to convince the Houthi rebels to stop their escalation,” Mr Saeed said. Meanwhile, Fatima Alasrar, a non-resident scholar at the Middle East Institute, said the special envoy to Yemen has to work hard to stop the Houthis from advancing towards the province of Marib. "He interfered successfully to stop government forces and the coalition from entering Hodeidah, and he needs to do the exact same to prevent the Houthis from entering Marib. He also needs to pressure them to withdraw from Jawf," Ms Alasrar told <em>The National.</em>