The former Calvin Klein model, a native of the West African nation of Benin, is urging policymakers to support the treaty — 10 years in the making — which Oxfam says would prevent the irresponsible sale or lease of weapons and ammunition across borders and would close loopholes.

“I see a number of my African brothers and sisters have been killed,” he says solemnly. “It’s ravaging the continent.”

More than 150 countries are gathering at the United Nations this week to restart negotiations on the treaty.

While Hounsou says many lawmakers have been “receptive” to his lobbying efforts, the entertainer admits some of them, “Seem to be a little bit jaded almost, honestly. I guess they deal with so many policies and issues like this.”

The two-time Academy Award nominee says, perhaps surprisingly, many of the people he met with in South Sudan recognized him from his role opposite Leonardo DiCaprio in 2006’s “Blood Diamond.”

He said of being a celebrity in the war-torn country, “You can’t help to feel a certain obligation to give something.

Photo: Djimon Hounsou during his March 2013 trip to South Sudan. / Courtesy Oxfam America