Addressing reporters at the world body's headquarters in New York on Friday, the secretary-general said the warring parties must seize on the "opportunity for peace" presented by UN-brokered talks scheduled to be held in Sweden later this month.
"First, violence must stop everywhere - with an immediate halt around critical infrastructure and densely populated areas," Guterres said, echoing a similar ceasefire call issued by the United States earlier this week.
"We must do all we can now to end human suffering and avoid the worst humanitarian crisis in the world from getting even worse," he added.
A US-backed Saudi-UAE military coalition launched an intervention in 2015 in the form of a massive air campaign aimed at reinstalling Hadi's government.
According to the UN, at least 10,000 people have been killed since the coalition entered the conflict. The death toll has not been updated in years, however, and is likely to be far higher. The Armed Conflict Location and Event Data Project (ACLED), an independent watchdog, recently said around 56,000 Yemenis had been killed in the violence.
In his comments to the media, Guterres also called for an increase in foreign aid and for "food, fuel and other essentials" to be allowed to enter Yemen "without restrictions" in order to alleviate the suffering endured by the 22 million Yemenis deemed by the UN to be in need of humanitarian assistance.