GENEVA (AFP) - The UN on Tuesday (Nov 7) urged the Saudi-led coalition to end a blockade which has halted the flow of humanitarian supplies into Yemen, further threatening some seven million people facing famine-like conditions.

"If these channels, these lifelines, are not kept open, it is catastrophic for people who are already in what we have already called the world's worst humanitarian crisis," a spokesman for the United Nations humanitarian office OCHA, Mr Jens Laerke, told reporters in Geneva.

Relief supplies into Yemen have been blocked since the coalition sealed off the country's borders following a missile attack last weekend by Yemen's Houthi rebels that was intercepted near Riyadh airport.

"Fuel, food and medicine imports must continue to enter the country," Mr Laerke said. "This is an access problem of colossal dimensions."

In the immediate aftermath of the blockade, fuel prices have jumped up to 60 per cent and cooking gas prices have doubled, the UN spokesman added.

OCHA is in talks with the coalition to restore access as soon as possible, Mr Laerke said.

The Saudi-led Arab military coalition intervened in Yemen in 2015 to support President Abedrabbo Mansour Hadi after the Houthis forced him into exile.

Last month, the United Nations put the coalition on its blacklist for killing and maiming 683 children during the conflict in 2016 and for carrying out 38 verified attacks on schools and hospitals.