By Shashank Bengali
Knight Ridder Newspapers

NAIROBI, Kenya — The difficult relationship between the Sudanese government and aid workers who are trying to help some 2 million refugees in Darfur worsened this week. Aid workers say authorities are imposing greater restrictions on relief operations as violence in the region escalates and tens of thousands more people flee their homes each month.

In the latest developments, a top humanitarian official was denied a visit to the war-torn Darfur region, and the relief agency that is managing Darfur's largest refugee camp was suddenly told it must leave the region.

Because of a lack of security and dwindling money, relief agencies say they can't reach 30 percent of the refugees in Darfur, the lowest level of access in two years.

"We have no security for our work," Jan Egeland, the United Nations' emergency relief coordinator, said Friday in Nairobi. "We are witnesses to massive attacks against the civilian population."

Egeland said 200,000 more people in Darfur had fled their homes in the past three months in response to continuing attacks by government-sponsored Arab militias called the janjaweed. Sudanese authorities armed the militias in 2003 to quell an uprising by Darfur's predominantly black population. The militias' campaign has left at least 200,000 people dead, most from disease and starvation.

This week, Sudan refused to allow Egeland to visit Darfur. Authorities gave multiple reasons, including that Egeland's native country, Norway, had published the controversial cartoons depicting the Prophet Muhammad this year. Egeland said Sudan, a largely Muslim country, didn't want him to see how bad things in Darfur had become.

The move earned widespread condemnation from the U.N., the U.S. State Department and other diplomats. Sudan is at odds with much of the international community over the U.N.'s plan to take over peacekeeping operations this year from the African Union, whose underfinanced force of 7,000 troops has been unable to stem the violence.

Sudanese authorities later said Egeland could reschedule his visit, but he said Friday that he hadn't decided whether to return.

Sudan also expelled a leading relief agency, the Norwegian Refugee Council, from Darfur this week for unspecified reasons. The council coordinated relief efforts in the Kalma camp in southern Darfur, which is home to 100,000 displaced people.