The International Criminal Court issued an arrest warrant Wednesday for Sudanese President Omar al-Bashir on charges of war crimes and crimes against humanity in Darfur. He is the first sitting head of state the court has ordered arrested.

Al-Bashir's government denounced the warrant as part of a Western conspiracy aimed at destabilizing the vast oil-rich nation south of Egypt. The U.N. said Sudan had ordered the expulsion of six to 10 humanitarian groups from Darfur including Oxfam, Solidarities and Mercy Corps, and seized assets.

U.N. Secretary-General Ban Ki-moon called the move a "serious setback to lifesaving operations in Darfur."

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Sudanese Vice President Ali Osman Mohammed Taha confirmed that 10 "associations" were asked to stop operating in Sudan for "because they violated laws and regulations."

He said "whenever an organization takes humanitarian aid as a cover to achieve a political agenda that affects the security of the county and its stability, measures are to be taken by law to protect the country and its interests."

Prosecutor Luis Moreno Ocampo had accused Sudanese troops and the janjaweed Arab militia they support of murdering civilians and preying on them in refugee camps. He said the militia also waged a campaign of rape to drive women into the desert, where they die of starvation.

But the three-judge panel in The Hague said there was insufficient evidence to support charges of genocide in a war in which up to 300,000 people have died and 2.7 million have fled their homes.

"He is suspected of being criminally responsible ... for intentionally directing attacks against an important part of the civilian population of Darfur, Sudan, murdering, exterminating, raping, torturing and forcibly transferring large numbers of civilians, and pillaging their property," court spokeswoman Laurence Blairon said. If al-Bashir is brought to trial and prosecuted, he faces a maximum sentence of life imprisonment.

Blairon rejected accusations that the warrant was part of a political plot and said the decision was made purely on legal grounds.

But African and Arab nations fear the warrant will destabilize the whole region, bring even more conflict in Darfur and threaten the fragile peace deal that ended decades of civil war between northern and southern Sudan. China, which buys two-thirds of Sudan's oil, supports the African and Arab positions.

Some African nations reportedly threatened to pull out of the court in retaliation for a warrant. Thirty African countries are among the court's 108 member states.

In a show of defiance Tuesday in anticipation of the decision, al-Bashir told supporters at a rally, "We are telling them to immerse it in water and drink it," a common Arabic insult meant to show extreme disrespect.

Hundreds of Sudanese waving pictures of the president and denouncing the court quickly turned out in a rally at the Cabinet building in Khartoum. Security was increased around many embassies, and some diplomats and aid workers stayed home amid fears of retaliation against Westerners.

The U.N., which has a joint peacekeeping mission in Darfur with the African Union, will continue to deal with al-Bashir, U.N. spokeswoman Michele Montas said at U.N. headquarters in New York.

"President al-Bashir is the head of state of Sudan, and United Nations officials will continue to deal with president al-Bashir when they need to do so," Montas said.

Al-Bashir denies the war crimes accusations and refuses to deal with the court. Sudan does not recognize its jurisdiction and refuses to arrest suspects and there is currently no international mechanism to arrest al-Bashir. The main tool the court has is diplomatic pressure for countries to hand over suspects.

U.N. peacekeepers and other international agencies operating in Sudan have no mandate to implement the warrant, and Sudanese officials have warned them not to go outside their mandates.

The United States is not a member of the international court, but Susan Rice, the U.S. ambassador to the United Nations, told The Associated Press, that "the United States supports the ICC action to hold accountable those who are responsible for the heinous crimes in Darfur."

"Those who committed atrocities in Sudan, including genocide, should be brought to justice," she said.

The EU welcomed the court's decision to issue an arrest warrant for al-Bashir and urged Khartoum to cooperate "fully and provide any necessary assistance to the Court."

Ocampo suggested al-Bashir could be arrested if he flies out of Sudan.

"As soon as Mr. al-Bashir travels in international airspace, his plane could be intercepted and he could be arrested. That is what I expect," the prosecutor said.

"Like Slobodan Milosevic or Charles Taylor, Omar al-Bashir's destiny is to face justice," Moreno Ocampo said referring to the former presidents of Yugoslavia and Liberia who were indicted while in office and ended up on trial in The Hague.

Asked why judges, in a 2-1 split decision, did not issue the warrant for genocide, Blairon explained that genocide requires a clear intent to destroy in part or as a whole a specific group.

"In this particular case, the pretrial chamber has not been able to find there were reasonable grounds to establish a genocidal intent," she said.

She said prosecutors could ask again for genocide charges to be added to the warrant if they can produce new evidence. Prosecutor Luis Moreno Ocampo said he would study the ruling before deciding whether to keep pursuing genocide charges.

The war in Sudan's western Darfur region began in 2003, when rebel ethnic African groups, complaining of discrimination and neglect, took up arms against the Arab-dominated government in Khartoum. In 2005, the U.N. Security Council asked Moreno Ocampo to investigate crimes in Darfur.

"With this arrest warrant, the International Criminal Court has made Omar al-Bashir a wanted man," said Richard Dicker, director of the International Justice Program at Human Rights Watch. "Not even presidents are guaranteed a free pass for horrific crimes. By ruling there is a case for President al-Bashir to answer for the horrors of Darfur, the warrant breaks through Khartoum's repeated denials of his responsibility."

The Rome statute that set up the International Criminal Court allows the Security Council to vote to defer or suspend for a year the investigation or prosecution of a case. It also gives the council authority to renew such a resolution.

The 52-member countries of the African Union and 26 states of the Arab League make up about a third of U.N. member states and they have said they would call for such a suspension.

But the council is sharply divided on suspending the case and is unlikely to take any action.