(CNN) -- Separatist rebels who captured northern areas of Mali called a cease-fire starting Thursday, saying they had captured key territory and achieved their military mission.
The Azawad National Liberation Movement (MNLA) said the rebels had captured enough of Mali's vast Sahara region to put down their guns.
The online statement said the MNLA "decides unilaterally to proclaim an end to military operations as of Thursday, April 5 at midnight GMT."
The Tuaregs consider the area, which they call Azawad, as the cradle of their nomadic civilization and launched an insurgency in January to achieve a separate homeland. The conflict has uprooted more than 200,000 people from their homes.
Buoyed by the chaos after last month's military coup that toppled the government, the rebels swept through the north with relative ease and wrested control of several strategic cities, including Kidal, Gao and Timbuktu.
"In all liberated regions, may it be in Kidal, Gao or Timbuktu, the MLNA today constitutes the sole authority providing security to the population," MNLA spokesman Mossa Ag Attaher told CNN affiliate BFM-TV.
The rebels have effectively split the West African nation in two, and northern areas remain volatile and tense, preventing aid agencies from accessing displaced people, the United Nations refugee agency said Thursday.
Thursday, the regional group, Economic Community of West African States, met in the Ivorian capital, Abidjan, to discuss military intervention in Mali.
The MLNA, however, warned ECOWAS against the deployment of troops.
Attaher told BFM-TV that the rebels have at least 3,000 fighters and any intervention "would be a disaster."
After the March 22 coup, Mali, long a shining example of democracy and stability in Africa, plunged into crisis.
Amnesty International said northern Mali was teetering on the brink of disaster. Kidal, Gao and Timbuktu have experienced days of looting, abductions and chaos since they were occupied by armed groups late last week, the human rights group said.
"All the food and medicine stored by major aid agencies has been looted, and most of the aid workers have fled," said Gaetan Mootoo, Amnesty International's researcher on West Africa.
"Women and girls particularly are too terrified to leave their homes. People are describing an atmosphere of near total lawlessness," Mootoo said.
In Gao, water and electricity have been cut and the hospital looted, Amnesty reported. Shops are shuttered, and people are surviving on meager food supplies.
"Medicine has been stolen and the records of the patients destroyed," a doctor told Amnesty. "In a few days, years of medical efforts and success have disappeared in the flames."
The Algerian consul in Gao and six employees were forcibly taken from the consulate and are being held by unidentified groups, the Algerie Presse Service reported.
"The Algerian government is totally mobilized for their liberation as soon as possible," said Algerian Foreign Minister Mourad Medelci.
In Kidal, Ansar Dine, an Islamist faction of the secular MNLA, has asked women to wear veils and destroyed a nightclub, Amnesty said. Ansar Dine is intent in imposing Sharia, or Islamic law.
In Timbuktu, Ansar Dine arrested and detained people accused of robbery and looting. Amnesty said it was concerned the group would mete out punishments in accordance with Sharia.
"The town is emptying out," a Timbuktu resident told Amnesty. "People are going to the south or to Mauritania. They are using all means: by car, by motorbike or on the donkeys."
Meanwhile in the capital, Bamako, military leaders who overthrew President Amadou Toumani Toure because of his alleged inability to handle the Tuareg rebellion postponed plans Thursday for a national convention aimed at addressing political woes. The reason remained unclear.
Military leaders had planned to invite political parties and civilian representatives to the convention, said Capt. Amadou Sanogo, the junta leader.
The international community -- including West African states, the African Union and the United States -- has called for the immediate restoration of constitutional rule. The African Union and ECOWAS have also slapped the military junta with travel and economic restrictions and have frozen its assets.
ECOWAS imposed a diplomatic and financial embargo, said Ivory Coast President Alassane Ouattara, who is chairman of the group.
"All diplomatic, economic, financial measures and others ... will not be lifted until the re-establishment of constitutional order," he said.
Sanctions targeted the supporters and relatives of the military junta and all those involved in contributing to the "destabilization" of Mali, the African Union said.
Under the sanctions, five neighboring nations will close their borders to landlocked Mali except for humanitarian purposes and deny the nation access to their ports, freeze its accounts in regional banks and suspend its participation in cultural and sporting events.
Now, Mali has no no access to the sea, is heavily dependent on foreign aid and faces a future of uncertainty.
CNN's Moni Basu contributed to this report.