Yemen’s warring parties are set to lay down their weapons for the first nationwide truce since 2016 on Saturday with all eyes on whether the UN-brokered ceasefire will hold. The Iran-backed Houthi rebels and Saudi-led coalition have both agreed to observe the two-month truce, which is to take effect at 16:00 GMT on the first day of Ramadan. Yemen’s intractable war has killed hundreds of thousands directly or indirectly and displaced millions, triggering the world’s worst humanitarian crisis, according to the United Nations. Previous ceasefires have been ineffective. A national truce ahead of p…