The United Nations has lifted famine declarations in three parts of Somalia, but warns that a quarter-million people still face “imminent starvation” in the region.

The U.N. Food Security Nutrition Analysis Unit said Friday that the Somali regions of Bay, Bakool and Lower Shabelle have been downgraded to a “Phase 4 – Emergency” status through December.

But three other regions in southern Somalia, including parts of the capital, Mogadishu, remain famine zones.

The agency said that humanitarian assistance has helped improve the “most extreme food deficits” in the regions and and reduced mortality levels.

But it warns much of the country will remain at an emergency level through 2012 because of the possibility of a below average harvest.

The U.N. says that tens of thousands of people have died since April, and that more deaths are likely in the coming months.

The famine declarations followed a severe and prolonged regional drought that left some 12 million people in need of emergency food aid.

Initial efforts to bring aid to Somalia were hampered by militant group al-Shabab, which restricted international relief efforts in many of the areas they control.

While the agency says the massive scale-up in aid since September has lowered malnutrition and mortality, it says death rates, especially for young children, remain “extremely high” in many regions of Somalia.

It also says that the amount of people who need emergency food aid is likely to remain at its current level of 4 million for the coming nine months.