New South Sudan Government Sworn In

South Sudan's President Salva Kiir has appointed a new government of national unity, bringing together politicians from opposite sides of the country's civil war.

Kiir named 30 ministers, 10 of whom were chosen by rebel leader-turned-Vice President Riek Machar and other political groups. The ministers were sworn in Friday at a ceremony in the capital, Juba.

The new government’s formation marks a major step toward implementing a peace agreement Kiir and Machar signed last August.

The peace deal calls for the transitional government to enact economic and military reforms, shepherd the country to elections within 30 months, and cooperate with a hybrid court that will try alleged perpetrators of atrocities committed during the war.

South Sudan's President Salva Kiir, center, laughs with First Vice President Riek Machar, left, and Vice President James Wani Igga, right, while cabinet members stand behind them, after the first meeting of a new transitional government of national unity,

Most of the ministers are well-known officials who have been on South Sudan's political scene for years. But there remain serious doubts the team can work together peacefully to move the country forward.

South Sudan erupted into civil war in December 2013, six months after Kiir fired Machar as vice president. Tens of thousands of people have been killed and more than two million others displaced from their homes since then.

Machar returned to Juba on Tuesday to retake his vice presidential post.

Aid agencies warn that despite the peace deal, the world's youngest country is at the edge of a humanitarian disaster, caused by poor harvests and food shortages since the start of the war.

They have called on the transitional government to allow unrestricted access to needy populations.

The U.S. government warned this week that it will impose sanctions on South Sudan's leaders if they fail to cooperate in the new government.