Yemen’s warring parties should revive efforts for a broader deal to end its devastating seven-year conflict, the country’s top United Nations envoy said on Tuesday after failed efforts to renew a truce deal on Sunday. The UN special envoy for Yemen Hans Grundberg told Reuters in Amman that this is a particularly sensitive period of time in Yemen. “Any small incident could spark something that could have devastating consequences.” “Luckily we have not seen a military escalation and this is so far so good,” he added. Grundberg said late on Sunday he would continue pushing for an extended and exp…