Top American officials called for a ceasefire in Yemen and demanded warring parties immediately come to the negotiating table.
The comments came as the Saudi-Emirati-led military coalition deployed more than 10,000 new troops towards a vital rebel-held port city in the run-up to a new assault.
James Mattis, the Pentagon chief, said the US had been watching the conflict "for long enough", adding he believes Saudi Arabia and the United Arab Emirates - who are in a US-backed coalition fighting Houthi rebels - are ready for talks.
"We have got to move toward a peace effort here, and we can't say we are going to do it sometime in the future," Mattis said at the US Institute of Peace in Washington.
"We need to be doing this in the next 30 days."
'Come to a solution'
US Secretary of State Mike Pompeo later called on the Saudi-Emirati coalition to stop air attacks in populated areas in Yemen. Pompeo said the "time is now for the cessation of hostilities" in the war-plagued country.
Mattis said the United States is calling for all factions to meet United Nations Special Envoy Martin Griffiths in Sweden in November and "come to a solution".
Saudi Arabia and its allies intervened in the conflict between embattled Yemeni President Abd-Rabbu Mansour Hadi, whose government is recognised by the United Nations, and the Houthis in 2015.
At least 10,000 people - a figure that hasn't been updated in years and is likely significantly higher - have since been killed and the country that now stands at the brink of famine that threatens an estimated 13 million.
The UN says Yemen could become the worst humanitarian catastrophe the world has seen in 100 years.