(Adds quotes from the top U.N. aid official)
By Denis Dumo and Tom Miles
JUBA/GENEVA, June 21 (Reuters) - More South Sudanese people are going hungry and 45,000 are still living in famine-like conditions even though South Sudan is no longer classified as being in famine, a U.N.-backed food security report said on Wednesday.
An estimated 6 million people, half the population, were expected to be in a "crisis, emergency or catastrophe situation" this month and next, 500,000 more than in May, the report by government and U.N. officials said.
"I do urge caution, as this does not mean we have turned the corner on averting famine," U.N. humanitarian chief Stephen O'Brien told a U.N. meeting in Geneva. "Across South Sudan, more people are on the brink of famine today than were in February."
The report, using a globally recognised system for classifying food security crises, said famine in the north had been halted by a swift influx of aid since March but there were now concerns about a region in the east bordering Ethiopia.
Areas rescued from famine would easily slip back into famine if aid was diverted to new hotspots, the report said.
O'Brien said U.N. appeals for funds had been largely unsuccessful, and the situation in South Sudan, but also Yemen, northeast Nigeria and Somalia, was "dire".
Deepmala Mahla, South Sudan director at aid agency Mercy Corps, said the overall situation was rapidly worsening.
"What this new report reinforces is that we have a very short window of time between someone being very hungry, to being on the brink of starvation," she said in a statement. "We cannot wait for people to be starving to act."
Two years after emerging as an independent state, the oil-rich country was plunged into conflict in December 2013 as rivalry between President Salva Kiir and his then-vice president, Riek Machar, turned into violence.
Since then, fighting has often been along ethnic lines and the conflict has triggered Africa's worst refugee crisis, with more than 3 million people fleeing their homes.
It has also prevented many farmers from planting and harvesting crops. Hyperinflation, which hit more than 800 percent last year, has put the price of imported food beyond the reach of many.
"Even though no county has been classified under famine ... this situation continues to be very critical," Isaiah Chol Aruai, chairman of National Bureau of Statistics, said in Juba as the report was released.
(Additional reporting by Stephanie Nebehay; Editing by George Obulutsa and Louise Ireland)
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