The US has called for a quick end to hostilities in Yemen, where three years of civil war have caused the worst humanitarian crisis in the world.
Defense Secretary James Mattis said all parties would have to attend UN-led peace talks within the next 30 days.
Secretary of State Mike Pompeo called on the Saudi Arabia-led coalition, which is fighting against the rebel Houthi movement, to end their air strikes on populated areas.
The US is under increasing pressure to stop supporting the coalition.
UN human rights experts say coalition forces may have committed war crimes in Yemen, and humanitarian organizations say their partial blockade has helped bring 14 million people to the brink of famine.
The assassination of US journalist Jamal Khashoggi by Saudi agents this month in Istanbul has also weighed on relations between Washington and Riyadh.
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Why is there a war in Yemen?
Yemen was devastated by a conflict that escalated in early 2015 when the Houthis seized control of the West and forced President Abdrabbuh Mansour Hadi to flee overseas.
Alarmed by the rise of a group they saw as representing Iran, the UAE, Saudi Arabia, and seven other Arab states intervened to restore the government. They have received logistical and intelligence support from the US, UK and France.
According to the United Nations, at least 6,660 civilians were killed and 10,560 injured in the fighting. Thousands of civilians died of preventable causes, including malnutrition, disease and poor health.
What did the US officials say?
Mr. Mattis said Tuesday at the US Peace Institute in Washington that the US had been watching the conflict "long enough."
"We need to move towards peace, and we can not say we will do that sometime in the future, we have to do that in the next 30 days," he said.
Mr Mattis added that all sides were invited to meet UN Special Envoy Martin Griffiths in Sweden in November and to "find a solution".
In a separate statement, Pompeo called on the Houthis to stop rocket and drone strikes on Saudi Arabia and the United Arab Emirates and the Coalition to end air strikes on all populated areas in Yemen.
"It is time to end this conflict, replace the conflict with a compromise, and allow the Yemeni people to heal through peace and reconstruction," he added.
The Trump administration has previously supported Griffiths' mediation efforts and called for a political solution to the conflict, in line with UN Security Council 2216, which requires the Houthis to withdraw from all the territories they occupy and give up their heavy weapons. The Houthis have rejected the resolution.
Why the ceasefire in the US is great
By James Landale, Diplomatic Correspondent, BBC News
For months, the Trump administration has said little about this bloody conflict, and the Saudi allies have taken the lead. However, the remarks made by Mr Mattis and Mr Pompeo show that the US is engaging in ways that they have not done for some time.
So far, both the United States and the United Kingdom have refused to formally demand a ceasefire by the UN, while it was clear that neither side was willing to think about it. But that seems to have changed. The question is, of course, why?
Diplomats point to growing pressure from the US Congress to act before the elections. The US could also hope to use the backlash against Saudi Arabia for the murder of Jamal Khashoggi to put pressure on Riyadh to end the conflict. Some diplomats have even spoken of a Saudi compromise whereby Yemen is part of the rehabilitation of Crown Prince Mohammed Bin Salman, the de facto leader of the kingdom.
The big question is how Iran will react. Some diplomats have suggested that Tehran would not be unhappy to resign from Yemen, that its commitment there is always opportunistic and not strategic, and that it has greater priorities elsewhere. However, it is not clear whether Iran would be prepared to help the US impose sanctions on its economy after withdrawing from the Iranian nuclear deal.
The US movement is important, but there is still a long way to go before a ceasefire becomes possible, let alone a political process to end the conflict for good.
How was the reaction?
There was no immediate response from the Saudi-led coalition, the Houthis or Yemeni government.
However, the head of the United Nations International Rescue Committee, former British Foreign Secretary David Miliband, said Washington's call for a ceasefire was "big news."
"I hope this represents an outburst of common sense in the US government, which is after all the key player when it comes to the decisions of the coalition led by Saudi Arabia," he told the BBC.
He also said Britain, China and Russia "should be ashamed of their silence". "Where do their statements repeat what Mike Pompeo and Jim Mattis have finally said," he asked.
British Foreign Minister Alistair Burt told a parliamentary committee on Tuesday that the British government was pressing for a political solution to the Yemen conflict, but would not suspend arms sales to Saudi Arabia.