The organisation in a statement on Saturday said 419,804 suspected cases of cholera have been reported since Apr 27, reports Xinhua news agency.

The highest number of fatalities was reported from the province of Hajjah and the Red Sea port city of Hodeida, according to WHO.

The epidemic has been "increasing at an average of 5,000 a day", the statement said.

The International Committee of the Red Cross has expected the suspected cases of cholera in Yemen to reach 600,000 by the end of 2017.

Jamie McGoldrick, the UN humanitarian coordinator for Yemen, said the cholera outbreak is "entirely man-made and is as a result of the conflict".

More than two years into war, Yemen is facing a total collapse, where two thirds of the total population, around 19 million, need humanitarian aid.

About 10.3 million people are at risk of famine and 14.5 million lack access to safe drinking water.

Fewer than 45 per cent of the country's hospitals are operational, but even the operational ones are coping with huge challenges, especially the lack of medications, medical equipment and staff, according to WHO estimates.

The blockade on Yemen, as part of a Saudi-led bombing campaign launched in March 2015, has deepened the crisis in the country which used to import most of its basic needs.