A man accused of coordinating Sudan's Janjaweed (search) militia is a legitimate tribal leader, and attempts to pursue him could lead to the "dismemberment" of the country, a top Sudanese official said.

The U.S. State Department has named Sheik Musa Hilal (search) and six other Sudanese as suspected coordinators of the government-allied Janjaweed, the Arab militia largely blamed for the violence in Darfur.

But Sudan's state minister for foreign affairs defended Hilal as a prominent tribal chief. Hilal "has nothing to do with the Janjaweed. He is a tribal leader, of a very big, very significant tribe," Minister Najeib el-Kheir Abdelwahab said in an interview Tuesday.

Sudan welcomed any international attempt to pinpoint Janjaweed leaders, Abdelwahab said. But "by not adequately identifying the leaders of the Janjaweed, by pointing to some tribal leaders ... if we are not cautious about that, you will ignite a significant tribal conflagration."

"And this can lead ... to the dismemberment of Sudan," the Sudanese minister warned.

Separately, the U.N. refugee chief said Khartoum has agreed to a stepped-up U.N. civilian role and possible expansion of an African Union monitoring team in the western Sudanese region of Darfur (search), where 19 months of conflict have left more than 50,000 dead and uprooted 1.4 million.

Darfur's bloodletting started in February 2003, when two non-Arab African rebel groups launched attacks primarily on government and military targets to press demands for a greater share of power and resources for Darfur.

Hilal has led Darfur's Arab Um Jalloul tribe for the past two decades. According to some international officials, Hilal used government funds to rally Arabs and set up militia training camps to quash the rebellions.

The Sudanese military and Janjaweed militia are accused of bombing runs and horseback raids that destroyed non-Arab villages. Residents have been killed, raped and driven from their homes. The United States, European Parliament and others say the campaign amounted to genocide.

At the United Nations, Sudanese Foreign Minister Mustafa Osman Ismail said the Bush administration is inflating the severity of the situation by calling it genocide in a bid to deflect attention from Iraq.

He said the United States was describing the violence as genocide "because of an internal agenda linked to the elections, linked to the competition with the Democratic party to win the votes of African Americans."

International officials and many of Darfur's displaced say bombing in the region has eased or stopped in recent weeks, as the U.N. Security Council reviews the genocide accusation and decides whether to impose sanctions on Sudan's oil industry.

Meanwhile, the U.N. refugee chief ended a five-day mission to Sudan and said the Arab-dominated government has taken steps to lessen the violence.

But attacks persist, and Darfur's people now have "zero trust" in their government to protect them, said Ruud Lubbers, the U.N. High Commissioner for Refugees.

As a result, Sudanese leaders agreed to a stepped-up civilian U.N. role to monitor rights violations, including teams of women to investigate complaints of Darfur's women and girls, Lubbers told reporters.

Sudan also says it is open to discussing expansion of what is now a tiny, 80-man African Union monitoring force here, Lubbers said.

Looking ahead, the refugee chief again urged Sudan to consider giving Darfur autonomy, calling it the only long-term solution to the conflict.

"I think in the interests of my people (the refugees), they need to get signals that people are seriously talking about the future of Darfur — so it really needs to move forward," Lubbers said Tuesday.

Lubbers' call has gone further than that of any other international official and angered Sudan's government.

President Omar el-Bashir (search) skipped a meeting with Lubbers on Tuesday, and Vice President Ali Osman Taha instead attended, Taha aides said.

It was not clear if the change was a snub or a reflection of Sudan's unsteady political situation. The government said it had foiled a coup attempt against it earlier this month.

In Geneva, Louise Arbour, U.N. High Commissioner for Human Rights, said she would tell Secretary-General Kofi Annan that the U.N. should boost staff in Sudan.

"I will be advocating as forcefully as I can the need for an expansion of the international presence on the ground," Arbour said. "There are still very serious violations of human rights."