The Grand Ethiopian Renaissance Dam (GERD) has drawn the ire of Egypt and Sudan since construction began in 2011, with both fearing for their water resources
Observers have pointed out that logistical support usually comes from the military, which is largely tied up Tigray, leaving organisers short on manpower.
Grandi, the UNHCR head, visited Ethiopia, including the Mai Aini refugee camp, over the weekend for the first time since the conflict began in November. The camp is one of two camps in southern Tigray the UN has been able to access.
Ethiopia sees the dam as key to plans to become Africa's largest power exporter. Egypt, which gets more than 90% of its scarce fresh water from the Nile, fears the dam across the Blue Nile could devastate its economy.