After spending billions of dollars on humanitarian aid in South Sudan in recent years, the United States may be ready to call it quits.

"The Government of South Sudan has lost credibility, and the United States is losing patience," the White House said in a strongly worded statement on Tuesday. "The United States Government will not continue in a partnership with leaders who are only interested in perpetuating an endless war characterized by ethnically-motivated atrocities."

But while South Sudan's government has been accused of blocking critical humanitarian aid and prolonging endemic violence in the country, many observers warn that pulling American aid would only plunge the county into further disaster. "We are asking the United States not to abandon this country, because we need them," said a spokesman for South Sudan's Foreign Ministry to Reuters on Wednesday, a call echoed by humanitarian aid groups.

It's a far cry from the atmosphere in July 2011, when the streets of the South Sudanese capital of Juba filled with people celebrating the end of a violent, decades-long struggle for independence from Sudan — a movement that achieved its goal in large part because of support from the United States.

Washington, its partners and South Sudanese civilians wanted a success story. Instead, they got another civil war.

In December 2013, tensions between President Salva Kiir, from the Dinka ethnic group, and Vice President Riek Machar, a Nuer, exploded into conflict. Troops loyal to each man turned against each other in Juba, leading to mass executions of civilians and chaos that soon spread to the countryside. The fighting spiraled into a brutal ethnic war and has hardly slowed down since.

Meet Babacho Mama, former child soldier thinking of returning to the fight (The Washington Post)

At least 50,000 people have been killed in the war and millions more displaced. According to the United Nations, both South Sudanese authorities and rebels regularly prevent planes and trucks from delivering food and medicine to civilians, leading the United Nations to declare a man-made famine in parts of the country. South Sudan denies it is interfering with food aid.

Now the White House is reviewing all of its assistance programs for South Sudan, which includes humanitarian programs in refugee settlements outside the country as well as support for implementing a largely ignored 2015 peace agreement. The United States is "committed to saving lives," reads the White House statement but "must also ensure our assistance does not contribute to or prolong the conflict, or facilitate predatory or corrupt behavior."

Some humanitarians fear that cutting food aid to South Sudan would only result in an even more serious hunger crisis and will punish civilians instead of the government. The United Nations recently warned that without assistance, 7 million people — two-thirds of the country's population — could face severe hunger.

One former USAID official, who spoke on the condition of anonymity because she still works in the region, said that despite the massive U.S. investment in humanitarian assistance in South Sudan, the situation seems to be getting worse.

“The number of people in need are still going up, the levels of displacement are still increasing, and overall the number of people in the most dire stages of hunger are increasing,” the former official said. “Either the level of distress is still increasing so extraordinarily that the level of assistance can’t keep up  — or there are gross levels of diversion happening.”

The former official agreed that it's time for Washington to assess whether the money being invested in South Sudan is saving lives or perpetuating the conflict. "Sometimes we have to have tough love and draw lines in the sand to say these are the conditions under which we can reasonably provide assistance," she said.

But Payton Knopf, a former U.S. diplomat now at the United States Institute of Peace, said that it is unlikely Washington will cut humanitarian assistance altogether, especially considering the level of suffering inside the country. "I don't have any reason to believe that is something the administration would do, or think that there’s much appetite for that in Congress," he said.

The United States has already taken concrete steps against South Sudan. In February, Washington implemented an arms embargoresulting in the recall of the South Sudanese ambassador to Washington. Some officials close to Kiir have already been sanctioned, and, in March, the United States announced sanctions on 15 oil operators in the country.

Gordon Buay, the charge d'affaires at the South Sudanese embassy in Washington, said that the United States has been "impatient" with South Sudan. "They want results next week, but we are telling them there is nothing to be done next week," he told The Post.

Washington "will lose leverage in [South Sudan] if it becomes antagonistic toward the government," Buay warned. "Whether the U.S. likes it or not, the government will still be there. ... It's the U.S. who will be losing." 

Read more: