A/HRC/42/CRP.1 governors of several other governorates, with al-Zubeidi as President, bin Breik as deputy and armed support from United Arab Emirates-backed Security Belt forces.93 114. The humanitarian situation continued to worsen. In June 2017, the UN Security Council issued a statement expressing serious concern at the devastating humanitarian impact of the conflict and calling on all parties to allow unhindered access for humanitarian supplies and to facilitate access for essential imports of food, fuel, and medical supplies. It also called on all parties in the conflict to renew their commitment to a cessation of hostilities. 115. On 4 November 2017, the Houthis fired a missile from Yemen towards the Saudi Arabian capital, Riyadh. The Saudi air defence intercepted the missile over the city, but fragments reportedly landed in the area of King Khalid International Airport. 94 In response, Saudi Arabia intensified airstrikes across Yemen and as of 6 November announced a complete blockade of all Yemen borders – air, sea and land. All humanitarian aid was blocked from entering and humanitarian flights were grounded, stranding humanitarian workers inside Yemen.95 On 22 November, the coalition announced that it would allow humanitarian flights to resume to the capital, Sana’a, and “urgent humanitarian and relief materials” to begin moving to the Houthi-controlled port of al-Hudaydah. 116. From 28 November 2017, following continued tensions between the allied Houthis and former president Saleh, their forces clashed in Sana’a. On 2 December, in a televised statement, Saleh declared his split from the Houthis, calling on his supporters to take back the country and expressing a willingness to enter a dialogue with the coalition. On 4 December, Houthi fighters attacked Saleh’s house in Sana’a. Saleh was killed by the Houthis that day in disputed circumstances.96 117. On 21 January 2018, the STC, allied with the United Arab Emirates, declared a state of emergency in Aden and issued an ultimatum to President Hadi to dismiss his government, exacerbating tensions between coalition members. Following the expiration of their one-week deadline, and in response to President Hadi’s countermeasures to prevent gatherings and demonstrations and ban armed groups from entering Aden, on 28 and 29 January the STC and its supporters clashed heavily with pro-Hadi forces. Forces supported by the United Arab Emirates aligned with the STC took control of most of the city and surrounded the presidential palace in what President Hadi described as a “coup attempt”, though they were stopped from entering the palace by troops from Saudi Arabia. 118. From May 2018, Yemeni armed forces and groups backed by the United Arab Emirates began to mobilize for an offensive, which officially began on 13 June, as they moved towards al-Hudaydah city amid continued warnings from the United Nations and others of the potentially disastrous humanitarian implications. In mid-July, Yemeni armed forces in the north, with coalition air support, advanced into two districts in Hajjah Governorate, cutting off Houthi supply lines to Hajjah and Sa’dah governorates. Clashes broke out along the frontlines in Hajjah and Sa’dah as parties continued to fight for control of the strategically important parts of the governorates. 119. In early November 2018, fighting around al-Hudaydah city intensified before Yemeni armed forces and affiliated armed groups halted their offensive, on 13 November. One month later, under the auspices of the Special Envoy of the Secretary-General for Yemen, the parties reached an agreement, referred to as the Stockholm Agreement, for a ceasefire in Hudaydah city, plans for the handover of the ports of Hudaydah, Salif, and Ras ‘Issa, a mechanism for activating the exchange of prisoners and a statement of Sana’a Centre for Strategic Studies, “Federalism in Yemen: A Catalyst for War, the Present Reality, and the Inevitable Future”, February 2019, p. 20. 94 https://www.nytimes.com/2017/11/04/world/middleeast/missile-saudi-arabia-riyadh.html. 95 OCHA, “Yemen: Blockade continues to severely hamper humanitarian efforts to reach millions in desperate need”, 17 November 2017, available at: https://www.unocha.org/story/yemen-blockadecontinues-severely-hamper-humanitarian-efforts-reach-millions-desperate-need. 96 For further discussion, see Crisis Group, “Collapse of the Houthi-Saleh Alliance and the Future of Yemen’s War”, 11 January 2018. 93 27