The Sudanese government has lifted an aid embargo on parts of the Western Upper Nile region, once again permitting humanitarian food drops. International relief groups welcome the move, but they say access is "totally inadequate" to reach all the people in need.

United Nations officials recently voiced concern for about two million Sudanese who had been cut off from help since fighting flared in late March between government and rebel forces. They said the country's West Upper Nile region has a malnutrition rate of more than 40 percent.

So, officials of the U.N. children's agency, UNICEF, were pleased when the Sudanese government permitted aid flights to the region to resume on Sunday.

The spokesman for UNICEF's south Sudan project, Martin Dawes, says many humanitarian groups have worked quickly to try to bring in as much aid as possible. "But Western Upper Nile, we need access for a variety of humanitarian reasons, not only child protection," he said. "There is a huge displaced population running from their homes. We believe they are short of food and resources to survive. That is the problem we are dealing with at the moment."

Aid groups say that at times, both the Sudanese government and rebel groups that are fighting for autonomy in the south, block relief operations as part of the wrangling between the two sides.

The aid groups also criticize the United Nations, which they say should take stronger measures to challenge the government, and rebel decisions that stop humanitarian airdrops.

Relief agencies say that in recent years, more Sudanese have died from the effects of famine than the war itself.

They say the worst situation is in Sudan's Eastern Equatoria province, which borders Kenya and Uganda. They say people there have been denied access to any aid for the past three years.