U.N. Secretary-General Antonio Guterres urged Yemen's warring parties on Friday to seize the momentum for peace and avert what could be the world's worst famine in decades.

The U.N. chief's appeal came days after the Trump administration demanded a cease-fire and the launch of U.N.-led political talks to end the war between a Saudi-led coalition allied with Yemen's government and Houthi Shiite rebels backed by Iran. U.S. Defense Secretary Jim Mattis called for a halt to hostilities within 30 days.

Guterres urged the coalition and the Houthis "to overcome obstacles and resolve differences" at U.N.-facilitated talks later this month.

"Violence must stop everywhere," preferably immediately, he said.

But the secretary-general stressed that the U.N.'s immediate priority is to stop the bombing in populated areas and preserve critical infrastructure including in the key port of Hodeida, the main entry point for international aid and 70 percent of food imports that Yemen relies on.

Guterres spoke following the coalition's announcement earlier Friday that it bombed an air base adjacent to the airport in the rebel-held capital Sanaa allegedly being used by the Houthis to launch drone and ballistic missile attacks into Saudi Arabia. Intense fighting was also reported in Hodeida province.

"It is very important that no missiles or other forms of aggression are sent against Saudi Arabia, and it's very important to stop bombing in urban areas, and it's very important to preserve basic infrastructure," the U.N. chief said. "That is why we are appealing for the kind of military action that is taking place from both sides to end."

He said the United Nations is seeing more and more countries engaged in helping to create conditions for the warring parties to understand not only the need for a cessation of hostilities but for serious political discussions.

The diplomatic initiative is being driven by the increasing threat of famine, but also by international outrage over the murder of U.S.-based Saudi journalist Jamal Khashoggi which has put a spotlight on Saudi Arabia's role in the war in Yemen.

Russia's U.N. Ambassador Vassily Nebenzia told several reporters Friday that Moscow has "been advocating for the early, immediate cessation of hostilities wherever — in and around Hodeida, elsewhere, because we believe in a political solution."

"That's the only thing that can bring peace back to Yemen," he stressed.

Nebenzia said U.N. special envoy for Yemen, Martin Griffiths, is "working on a peace plan that might bring the parties together and finally finish this useless conflict" and Russia wants to hear from him "on new avenues that he's exploring."

The Security Council is expected to hear from Griffiths on Nov. 16 and diplomats say the U.S., Britain and France are drafting a resolution to support peace efforts and address the humanitarian crisis.

Nebenzia said there has been talk in the council about supporting the peace process. As to whether this is the right time, he said: "Possibly. Let's see. We know that pressure is being mounted from all sides on the parties to stop hostilities."

The conflict in the Arab world's poorest country began with the 2014 takeover of Sanaa by the Houthis, which toppled the internationally recognized government. A Saudi-led coalition allied with the government has been fighting the Houthis since 2015.

Civilians have borne the brunt of the conflict, which has killed over 10,000 people and sparked a cholera epidemic and the world's worst humanitarian crisis.

U.N. humanitarian chief Mark Lowcock warned last week that "there is a clear and present danger of an imminent and great big famine engulfing Yemen" that could affect 14 million people — half of the country's population.

"Yemen today stands on a precipice," Guterres said Friday, and "the urgency of the humanitarian crisis leaves no room for complacency."

He urged all countries to prevent "the already dire conditions from deteriorating into the worst famine we have seen in decades."

"My objective is to appeal to the parties to the conflict to understand that there is an opportunity that must be seized, and to say that the humanitarian situation is so dire that if that doesn't happen" the world will have to deal with a famine in Yemen next year, he said.

"I must say, I'm hopeful that the voice of reason will prevail," Guterres said.