A UN environment meeting opened in Nairobi on Monday under a dark cloud cast by the Ethiopian Airlines crash that killed 157 people, including at least 22 United Nations staff, many heading for the annual event.
Delegates arrived at the sprawling compound to see the UN flag flying at half-mast and the usually colourful display of national flags removed.
READ: Ethiopia mourns crash victims as investigators seek answers
As they wondered aloud who among their colleagues may have been on board the ill-fated Boeing, some hugged and comforted one another.
According to Maimunah Sharif, head of UN Habitat, at least 22 UN employees were among those who died when the Nairobi-bound Ethiopian Airlines jet crashed early on Sunday just six minutes after take-off from Addis Ababa.
"I stand before you on the first day of the UN Environment Assembly (UNEP), which has officially commenced today in the wake of this tragedy," she told delegates.
"We will not forget this tragedy, nor those who perished. Let us reflect that our colleagues were willing to travel and to work far from their homes and loved ones to make the world a better place to live."
A minute's silence
Kicking off the opening plenary, UN Environment Assembly President and Minister of Environment of Estonia, Siim Kiisler asked delegates, many dressed in black and some in tears, to observe a minute's silence.
"I would like to express my condolences to those who have lost loved ones in the crash," he said.
A member of the UNEP secretariat told AFP it was "still trying to consolidate" the number of staffers who died.
Among the UN staff were some who worked for the World Food Programme, the UN refugee agency (UNHCR), the International Organization for Migration and the Food and Agriculture Organization, the agencies have said.
The annual UNEP assembly gathers heads of state, ministers, business leaders and civil society representatives to work on ways to slash pollution and build a greener global economy.
Delegates in Nairobi must get to grips with a series of UN reports outlining in stark terms the damage mankind is doing to the planet.
One briefing on the eve of the summit said the cost of ecosystems loss through agriculture, deforestation and pollution was a much as $20 trillion (€17.7 trillion) since 1995.
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