Morgan Freeman, Jack Black and a host of other celebrities star in a video backing Americas' nuclear deal with Iran, wise-cracking their way through an often surreal mixture of Hollywood, politics and diplomacy.

George Clooney, the Hollywood actor, has launched a new initiative called The Sentry aimed at ending conflicts on the African continent by tracking the money that fuels them. The Sentry, founded by Clooney and John Prendergast from the advocacy group the Enough Project, will investigate the financing of conflicts in South Sudan, Sudan, the Central African Republic (CAR) and the Democratic Republic of Congo.

Bob Geldof’s Live Aid pioneered a new wave of stars’ involvement in the developing world that has produced mixed results. [...] Yet, as American journalist David Rieff has noted, Live Aid’s donations to NGOs such as Oxfam and Save the Children also facilitated the displacement of 600,000 people by the autocratic Mengistu regime, resulting in an estimated 100,000 deaths.

The duck suits and One Direction's online call "to put pressure on our leaders" are both part of a global effort to send a message to the Financing for Development summit that starts on Monday in Addis Adaba, Ethiopia.

Peng Liyuan, the celebrity wife of Chinese President Xi Jinping, has played a key role in successfully projecting the Communist giant's soft power abroad through her public diplomacy, according to a study on the country's first lady.

Ben Affleck made his way back to Capitol Hill on Thursday to testify on behalf of Eastern Congo in front of the Senate Appropriations Committee. The Oscar winner, who was joined by wife Jennifer Garner and philanthropist and Microsoft founder Billl Gates, spoke about his Eastern Congo Initiative in front of the State, Foreign Operations and Related Programs subcommittee hearing on diplomacy, development and national security to ask them to allocate some of their budget to the Democratic Republic of the Congo.

The risk of celebrity attachment is oversimplification of the problem and the potential solutions. Zambian economist Dambisa Moyo calls it "glamour aid". Heavily stylised photographs of stars sympathising with suffering masses are certainly a modern cliche.

The Havana excursion, which Team Coco’s editors are still furiously cutting together, represents a new form for him, an hour-long episode set to air March 4 where he is the perpetual “fish out of water” — an attempt to use comedy as a kind of diplomacy. “Maybe it's not a bad form of diplomacy. Maybe it's not bad to send a comedian over,” Conan said of the thawing U.S.-Cuba relations spearheaded by the Obama administration.