Just back from a two-week trip to 19 locations in Sudan's Darfur region, actor and UN messenger of peace George Clooney-despite his well-publicized recent run-in with male fashion model Fabio-arrived Thursday at the United Nations joking and shaking hands as he walked past hundreds of employees.

Clooney toured UN headquarters for a ceremony and a new pin on his lapel marking his designation for the special job by Secretary General Ban Ki-moon.

As the ninth UN 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.

New UN Messenger of Peace, George Clooney, speaks at news conference at United Nations headquarters in New York City. Clooney on Thursday appealed to Sudanese President Omar al-Beshir to allow the full UN-African Union peacekeeping force into strife-torn Darfur.(photo: Xinhua/AFP)

"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 US$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 UN role.

(Agencies via Xinhua February 2, 2008)