The war and blockade of Yemen has cost Saudi Arabia tens of billions of dollars, further aggravated the humanitarian crisis in the country and destroyed much of Yemen's infrastructure, but failed to dislodge the Shiite Houthi rebels and their allies from the Yemeni capital.[161][2] More than 50,000 children in Yemen died from starvation in 2017. From 2015 to May 2019 the number of total deaths of children is said to be approximately 85,000.[162][163][164][165] The famine in Yemen is the direct result of the Saudi-led intervention and blockade of the rebel-held area.[161][166] In October 2018, Lise Grande, the United Nations Humanitarian Coordinator for Yemen, warned that 12 to 13 million Yemenis were at risk of starvation if the war continued for another three months.[167] On 28 March 2018, Saudi Arabia, along with its coalition partner the UAE, donated US$930 million to the United Nations which, according to UN Secretary-General António Guterres, "...(will) help to alleviate the suffering of millions of vulnerable people across Yemen". The funds cover almost one-third of the $2.96 billion required to implement the UN's 2018 Yemen Humanitarian Response Plan.[168] Following the Houthi missile attack against Riyadh in December 2017, which was intercepted by Saudi air defence,[169] bin Salman retaliated with a ten-day barrage of indiscriminate airstrikes against civilian areas in Yemen held by Houthi forces, killing dozens of children.[170]