But the overall picture is one of improvement, the world body insisted Friday.
''We know there are needs that are not being met . . . [But] we are no longer worried about [whether] anyone is starving. The schools are reopening. That is a sure sign of recovery,'' Bo Asplund, the U.N. representative in Indonesia, said in Banda Aceh, the provincial capital.
Meanwhile, rebels and government officials in Indonesia and Sri Lanka planned talks to ease tensions and secure the safe delivery of relief to survivors. The Dec. 26 disaster killed between 145,000 and 178,000 people in 11 countries, most in Aceh, and left tens of thousands more missing and feared dead.
In Thailand, a two-day conference kicked off to draw up plans to set up a tsunami-warning network.
One U.N. report on the camps said conditions are appalling along Aceh's west coast. Some camps have no latrines, forcing people to defecate in fields or near rivers and ponds where they also bathe.
While Asplund acknowledged those concerns, he said the situation was ''well onto the path of recovery.''
''Some coastal communities - small ones - are still needing adequate food. . . . Other communities need better water and sanitation,'' he said.
The U.N. children's fund warned that 12.7 percent of children in Banda Aceh suffer malnutrition - which stunts growth, retards mental development and weakens the immune system. UNICEF said that figure was a ''critical emergency'' and warned that conditions could be even worse outside the provincial capital.
Jakarta and Acehnese rebels briefly set aside their three-decade conflict in the aftermath of the disaster. But now both sides accuse each other of renewed fighting that threatens to disrupt the international relief effort.
The two sides hoped to begin talks on a formal cease-fire Friday in Helsinki, Finland. Indonesia President Susilo Bambang Yudhoyono has offered rebels amnesty in exchange for a cease-fire, and wants them to drop independence goals. Moves are also under way in Sri Lanka to ease tensions between rebels and the government.