Swedish diplomat Hans Grundberg is set to become the next UN envoy to Yemen, where years of peacemaking efforts have failed to end a war and a deepening humanitarian crisis, diplomats said. The UN has not formally announced Mr Grundberg’s appointment, but he was congratulated on social media on Friday by two former Swedish foreign ministers, Margot Wallstrom and Jan Eliasson. UN Secretary General Antonio Guterres reportedly told UN Security Council members this month that he planned to hire Mr Grundberg, a Middle East specialist who has been the EU’s ambassador to Yemen since 2019. The career diplomat has also been posted to Cairo, Jerusalem and Brussels, where he headed a working group on the Middle East. He will replace Martin Griffiths as the UN’s fourth envoy to Yemen. Mr Griffiths, a Briton, was named in May as the UN’s next head of global humanitarian affairs. He has expressed “deep regret” for failing to end Yemen’s protracted conflict. The appointment comes amid fierce fighting in Yemen, with a Houthi rebel offensive on Marib, a hydrocarbon-rich region and the UN-recognised government’s last remaining stronghold in the north of the country. Conflict flared in Yemen in 2014 when Iran-backed Houthi rebels seized the capital Sanaa and toppled a leadership they saw as corrupt. Saudi Arabia the following year led an Arab military intervention to restore the ousted government. The war has forced millions of Yemenis to flee their homes, claimed hundreds of thousands of lives and tanked the economy. Four fifths of Yemenis rely on aid in what the UN calls the world's worst humanitarian crisis.