Saudi Arabia proposes five-day ceasefire in Yemen
Saudi Arabia says it is prepared to introduce a five-day humanitarian ceasefire in Yemen.
A Saudi-led coalition launched air strikes against Houthi rebels in Yemen six weeks ago. At least 1,400 people have been killed, the UN says.
US Secretary of State John Kerry said Saudi Arabia and Yemeni rebels are discussing when to start the ceasefire.
The Saudi foreign minister said any truce would depend on the rebels' co-operation.
Saudi Arabia insists the Houthis must lay down their arms for the humanitarian ceasefire to be implemented. The rebels have not yet responded to the appeal.
The Saudi-led coalition aims to restore the government of exiled President Abdrabbuh Mansour Hadi.
He fled the capital Sanaa in February and took refuge in the southern port city of Aden, before leaving for Saudi Arabia.
Sunni-ruled Saudi Arabia has accused Shia-led Iran of backing the Houthis, who are affiliated with the Zaidi sect of Shia Islam. Tehran denies the accusations.
Aden has seen some of the heaviest fighting in recent weeks, with hundreds of families reported to be trapped in the city centre with dwindling supplies.
Jens Laerke, a spokesman for the UN Office for the Co-ordination of Humanitarian Assistance, said at least 6,000 people had been injured in the fighting, many of them civilians in Aden.
"People in Aden have endured extreme hardship as a result of conflict over the last six weeks and must be able to move to safer areas to seek medical and other assistance," Mr Laerke said.
Analysis: Frank Gardner, security correspondent
The key word in Saudi Arabia's proposed ceasefire announcement in Yemen is "conditional".
It depends, say the Saudis, on Yemen's Houthi rebels laying down their weapons and stopping fighting. Even if their leaders agree to that condition, it is far from certain that will translate into a ceasefire on the ground.
The last time the Saudis announced a pause in their air strikes to allow humanitarian aid to reach civilians, the Saudis say the rebels took advantage of the lull to seize a major military barracks and advance further into the port of Aden. The air strikes then resumed.
The Saudis don't trust the rebels but they also know they can't keep bombing Yemen indefinitely.
At a press conference in the Saudi capital, Riyadh, Saudi Foreign Minister Adel al Jubeir said $274m (£180m) would be provided in humanitarian assistance.
However, on Wednesday, a statement by 22 aid agencies working in Yemen said a humanitarian pause would "not alleviate the humanitarian impacts of the current conflict".
The charities - who say their work is being hampered by a lack of fuel in Yemen - called instead for a permanent end to the fighting.
Also in Riyadh, Mr Kerry said the US and Saudi Arabia did not have plans to send ground troops into Yemen.
This is despite earlier pleas by Yemen's government to the UN to authorise the deployment of foreign ground forces.
A letter to the UN said Houthis were "targeting anything that moves" in Aden.