(IRIN) – Aid agencies are ringing loud alarm bells after the Saudi Arabia-led coalition closed Yemen’s land borders, sea ports, and airspace, warning of the extreme dangers of cutting off access and assistance to a country already on the verge of famine. The UN’s top relief official Mark Lowcock told reporters on Wednesday that if the new restrictions – now in place for three days – were not lifted, Yemen faces “the largest famine the world has seen for many decades”.