Sudan vowed on Wednesday it would not work with the International Criminal Court as thousands of protestors massed in Khartoum to protest at the arrest warrant against President Omar al-Beshir.
Security was beefed up around foreign embassies amid fear of reprisals by Beshir supporters, while diplomats urged expatriates to avoid public places and stock up on essential supplies.
The government remained defiant after the ICC announced the warrant against Beshir for war crimes and crimes against humanity including extermination, rape and pillaging -- the first by the court against a sitting head of state.
"We will not deal with this court," Justice Minister Abdel Basit Sabdarat told Al-Jazeera television. "It has no jurisdiction, it is a political decision."
In Khartoum, banner-waving crowds massed on the banks of the Nile, chanting "We love you President Beshir."
"We will protect President Beshir with every drop of our blood," chanted another group of demonstrators near Khartoum university.
One demonstrator, Fakri Osman, charged the West with hypocrisy, saying it had "two weights, two measures."
"We want a Sudanese solution to a Sudanese problem," he told AFP.
Ahead of the announcement, the Sudanese army broadcast a stark warning on state radio against anyone trying to exploit the court's decision.
"The armed forces will firmly deal with whoever cooperates with the so-called International Criminal Court, and uses it as a platform for political blackmail and for destabilising the security and stability of the country," spokesman Osman al-Aghbash said.
Sudanese media predicted that Wednesday's demonstration would be followed by larger rallies in Beshir's northern power base later in the week.
On Tuesday, thousands paraded portraits of Beshir at the inauguration north of the capital of the largest hydro-electric project built on the Nile in 40 years, where the president dismissed the ruling as worthless.
"It will not be worth the ink it is written in," he said.
Embassies asked their citizens to stay inside for fear of hostile protests.
"As a precaution in case of demonstrations which might inhibit movement, you are advised to maintain several days' stock of food and water," the British mission said.
Two military trucks were parked outside the French embassy, an AFP correspondent reported.
Some UN staff have been told to leave work early to avoid any potential demonstrations.
The medical aid organisation Doctors Without Borders (MSF) said it had pulled its expatriate staff out of Darfur after the Sudanese government ordered them to leave.
"The government of Sudan has ordered MSF to evacuate all of its international personnel from a certain number of projects in western and southern Darfur by March 4 at the latest," MSF said.
An MSF official said about 70 people including foreigners and Sudanese nationals who are not from Darfur were pulled out on Tuesday from four towns.
The joint UN-African Union peacekeeping force in Darfur (UNAMID) said its patrols are "operating as normal", but that its troops were "closely monitoring the state of affairs throughout the area".
However, sources within the mission said the situation was tense inside the western region.
"Our guys on the ground feel that there is tension. The Sudanese security forces are much more visible in Darfur," said a UNAMID official.
There is concern among the international community that protestors could direct their anger at foreigners.
The United Nations employs some 32,000 people in Sudan including local staff, and thousands of other nationalities also live there.
Darfur's most active rebel group, the Justice and Equality Movement (JEM), has threatened to step up efforts to topple Beshir if a warrant is issued and he fails to cooperate.
JEM leader Khalil Ibrahim said this week that his troops would retaliate if reprisals were taken against the people of Darfur.
"If they harm civilians, JEM will react," Ibrahim said. "Even in Khartoum, JEM is ready to protect the civilians."
The group's Cairo representative Mohammed Hussein Sharif hailed Wednesday's announcement.
"We consider this day a great day for the Sudanese and Darfur people, and we renew our call on Beshir to appear before the court to plead his innocence, if he were indeed innocent," he said.