Foreign donors must come forward to support Ethiopia and Eritrea after the long-time arch rivals ended a war which spanned two decades and hampered efforts to improve the lives of millions of people, a top United Nations official said on Monday.

Ahunna Eziakonwa, head of the U.N. in Ethiopia, said moves taken by the two east African neighbors to normalize ties in recent weeks had “sown seeds of hope” – but added that many challenges lay ahead on their road to recovery.

The two poor nations will have to remove landmines and rebuild infrastructure, especially along their border, where the conflict was concentrated.

They will also need to stimulate their economies and create jobs for the youth, say experts.

“I hope the international community will come forward to support these two countries. It is very important – not just for these two nations, but for regional peace and security,” Eziakonwa told the Thomson Reuters Foundation in an interview.

“It makes strategic sense – not just from the humanitarian perspective, but also from a security perspective – to rally behind this peace initiative and invest in a peace building process in a way that it touches on development transformation.”

Triggered by a border dispute in 1998, the conflict killed more than 80,000 people. At least 350,000 people living along the border on both sides were uprooted and forced to flee.

Meager resources meant to reduce poverty and improve basic services such as health and education were diverted to fund the conflict while schools, hospitals, power and water supplies were destroyed by shelling and artillery fire.