The 46-year-old actor arrived Thursday at the United Nations, joking and shaking hands and repeating "Hi guys!" as he stepped past hundreds of curious U.N. employees.
Clooney toured U.N. headquarters for a ceremony and a new pin on his lapel marking his designation for the special job by Secretary General Ban Ki-moon.
He was just back from a two-week trip to 19 locations in Sudan's Darfur region, the Central African Republic, Chad and the Democratic Republic of Congo, arriving in the U.S. by way of India, a major contributor of U.N. peacekeeping troops, U.N. officials said.
As the ninth U.N. peace envoy, the Oscar winner (best supporting actor for "Syriana") was selected for his ability to focus public attention on critical international political and social issues. He told reporters it was a tremendous honor for him.
"I am very proud to be here as a messenger of peace, and the message is: That the world is watching, and that at this point we cannot afford to fail," he said. "There's a lot more responsibility with this one than with an Oscar, which all you really have to do is, you know, drink after the party."
Clooney took on the job of promoting the world body's peacekeeping missions after waging his own campaigns for an end to the 4 1/2-year war in Darfur and for more humanitarian aid for the millions caught up in the conflict.
He is a co-founder of Not on Our Watch, a humanitarian group that focuses global attention on Darfur's people and has raised more than $9.3 million for the region.
Other messengers of peace are Michael Douglas, Elie Wiesel, Jane Goodall, Yo-Yo Ma, Daniel Barenboim, Paulo Coelho, Midori Goto and Princess Haya of Jordan.
Clooney said he plans to focus his attention on Darfur and other spots he knows best, but has ambitions to travel broadly in his U.N. role.
On his first trip this month as a U.N. messenger of peace, he joined Jane Holl Lute, the assistant secretary general of peacekeeping operations, as part of "a technical assessment mission" visiting the joint African Union-United Nations peacekeeping operation in Darfur and the U.N. missions in the other nations.
"It was planned in secret for obvious security reasons, and worse yet they might have seen some of my films," Clooney said.
He was accompanied on his visit to U.N. headquarters by his parents, Nick and Nina Clooney.
"I am the son of a newsman, so the job of messenger comes with the responsibility to deal with facts, not to tell people what they want to hear, but to tell them what the truth is, unfiltered," Clooney said.
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