GENEVA: Three cities in Yemen have run out of clean water because a blockade by a Saudi-led coalition has cut imports of fuel needed for pumping and sanitation, the International Committee of the Red Cross (ICRC) said on Friday.

As a result of the development in Taiz, Saada and Hodeidah close to one million people are now deprived of clean water and sanitation as Yemen emerges from the world's worst cholera outbreak in modern times, the ICRC said.

Other cities, including the capital Sanaa, are expected to be in the same situation within two weeks, ICRC said in a statement.

"With imports of fuel and other essential goods at a standstill for the past ten days, three Yemeni cities had to stop providing clean water in recent days, putting close to one million people at risk of a renewed cholera outbreak and other water-borne diseases," it said.

"The water and sewage systems in Hodeidah, Saada and Taiz stopped operating because of a lack of fuel," the head of the ICRC in Yemen, Alexandre Faite, said in the statement.

The coalition closed all air, land and sea access to Yemen on Nov. 6 following the interception of a missile fired towards the Saudi capital, saying it had to stem the flow of arms from Iran to its Houthi opponents in the war in Yemen.

The United Nations has said the blockade could lead to "untold thousands" of deaths, and that its partial lifting by the Saudi-led coalition is not enough.

Iolanda Jacquemet, an ICRC spokeswoman in Geneva, said the shutdown of water services was a very bad sign for the fight against cholera, which had been on the wane for weeks in Yemen, although new cases are still running at about 2,600 per day.

"We're very scared that cholera might come back," she said, noting that the huge outbreak, which has sickened over 900,000 people, started in the capital Sanaa in April just 10 days after the sewage treatment plant had stopped working for lack of fuel.

"If these water treatment plants and sewage plants stop working, it can only bring cholera back and other water-borne diseases," she said.

As medical supplies run down because of the blockade, ICRC staff had been approached for help by five medical centers that it does not normally support.

Already 7 million people are in "famine-like conditions", and the U.N. has said that number could rise to over 10 million if Yemen does not get food and nutritional supplies fast.

Famine is only officially declared after an inspection team has carried out a formal survey on the ground, so there is no guarantee that famine is not already underway.

"There may be, as we speak right now, famine happening," U.N. humanitarian spokesman Jens Laerke told a regular U.N. briefing in Geneva. "And we hear children are dying. There is excess mortality as a consequence of under-nourishment."