President Barack Obama says the ceasefire deal in South Sudan is a critical first step toward lasting peace.
Mr Obama welcomed the agreement struck yesterday between South Sudan's government and rebels.
He called on South Sudan's leaders to implement it fully and start a political dialogue to resolve the conflict's causes. He said it was critical that political detainees currently held by South Sudan's government fully participate.
The president said South Sudan's leaders must regain trust from their people and the world by demonstrating their commitment to a peaceful resolution.
He said they have an obligation to ensure the country's future is not marred by further violence and that those who committed atrocities are held accountable.
Five weeks of warfare in South Sudan has killed thousands of soldiers and civilians.