Oxfam on Saturday claimed that a further eight million people will be without running water due to fuel shortages arising from the Saudi-led blockade on the country's northern ports.
The coalition has given the United Nations permission to resume flights of aid workers to the Houthi-controlled capital, but not to dock ships loaded with wheat and medical supplies, a UN spokesman said.
Recent mass arrests in an anti-corruption drive led by Prince Mohammed, which saw dozens of princes, former officials and media tycoons held in Riyadh's Ritz-Carlton, are largely seen as an attempt to consolidate his power since becoming crown prince two and a half years ago.
Prince Mohamed has also touted his programme of modernisation, which has included curbing the power of Saudi's religious police and preparing to allow women to drive and attend football matches.
He repeated to the New York Times his pledge to tackle the intolerant, puritanical brand of Islam of Saudi Arabia's Wahhabi clerics, and return Saudi Islam to the more open orientation that was eclipsed by fundamentalism in 1979, the same year Iran saw its own Islamic revolution.
"We are 'restoring' Islam to its origins — and our biggest tools are the Prophet's practices and [daily life in] Saudi Arabia before 1979," he said. According to many of the records of life during the Prophet Muhammad's time around 570-632 CE, women and men mixed more freely than they do in Saudi Arabia today, and Islam existed alongside Judaism and Christianity.
The promise of a return to a more moderate Islam is coupled with a bid to encourage economic growth, and the kingdom hopes it will help Saudi Arabia's bid to carve out greater influence regionally and internationally.
The speed of Prince Mohammed's reforms may have challenged older generations in the slow-moving kingdom, but are designed to reach out to younger Saudis.
There are, however, concerns about his sweeping corruption crackdown, seen as a purge as he tightens his grip on power. Many see the arrests of dozens of princes as a warning shot to those who may pose a challenge to the future king, and an attempt to silence all but his most loyal associates.
This article originally appeared on the Daily Telegraph