Hollywood actor George Clooney has been appointed the ninth UN messenger of peace.

"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," he said.

Clooney had just returned from a two-week trip to 19 locations in Sudan's Darfur region, the Central African Republic, Chad and the Democratic Republic of Congo.

He is a co-founder of Not on Our Watch, a humanitarian group that focuses global attention on Darfur's people. He has raised more than $9.3 million (£4.6 million) for the region.

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.

Other messengers of peace include Michael Douglas, Elie Wiesel, Jane Goodall, Yo-Yo Ma, Daniel Barenboim, Paulo Coelho, Midori Goto and Princess Haya of Jordan.

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