Kai Ryssdal: While Facebook was underperforming in New York but still creating instant millionaires in Silicon Valley, world leaders focused on the other end of the socio-economic spectrum today.

Ahead of the G8 summit this weekend, President Obama said the world’s richest country has a moral obligation to lead the fight against hunger and malnutrition. He also said government can’t do it alone, and that he’s lined up $3 billion from the private sector to help out — which raised a few eyebrows.

From the Marketplace Wealth and Poverty Desk, Krissy Clark explains.

Krissy Clark: First, Obama made the announcement about partnering up with companies like PepsiCo and Monsanto to lift 50 million people from poverty over the next decade. But as soon as he made it, he was already anticipating the follow-up question.

President Obama: I know some have asked in a time of austerity, whether this new alliance is just a way for governments to shift the burden on to somebody else. I want to be clear: the answer is no.

Gregory Adams with Oxfam says he hopes the president’s right. He’s one of the people who’s concerned that recently, there’s been a push to get governments out of the way when it comes to food and agriculture problems in poor countries, and let private investment solve them instead. That, Adams says, leaves some big gaps.

Gregory Adams: There are some very basic infrastructure functions that the private sector just has not shown they just can do by themselves. Things like agriculture extension services, roads, consistent water supply.

Raj Shah: That said…

Raj Shah heads U.S AID for the Obama administration.

Shah: The private sector brings some incredibly unique technologies and business models that simply can’t be replicated by public sector investment alone. Vodaphone, for example, is committing to reach 500,000 small scale farmers with SMS text-based services that would allow them to ascertain local market prices.

That helps farmers negotiate better deals at the market. Shah says the private efforts are meant to supplement the fight against global hunger, not replace it. But ultimately, that’ll be up for the world leaders at the G8 conference this weekend to decide.

I’m Krissy Clark for Marketplace.