The move comes as M23 militants continue to seize key towns in their latest offensive despite widespread calls for a ceasefire

The Southern African regional bloc has announced a "phased withdrawal" of its troops from the Democratic Republic of the Congo (DR Congo), where they have been deployed to help fight armed groups in a country that has endured decades of violence.

The decision comes amid heavy fighting in DR Congo's eastern provinces between the Congolese Army and militants from the M23 group, who have seized major towns in their latest offensive since the beginning of the year.

More than 8,500 fatalities have been recorded in the hostilities, according to official figures. At least 20 peacekeepers from the Southern African Development Community (SADC), including Malawian, Tanzanian, and South African soldiers, have also been killed.

On Thursday, leaders from the 16-nation SADC held a virtual summit and expressed "grave concern" about the "continued deterioration" of the neighboring country's security situation, including the blockage of main humanitarian aid supply routes.

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In an official statement after the meeting, the regional authority said it has "terminated the mandate of SAMIDRC [Southern African Development Community Mission in the DRC] and directed the commencement of a phased withdrawal" of troops.

The group, however, pledged to continue to "support interventions aimed at bringing lasting peace" and the DR Congo's "pursuit of safeguarding its independence, sovereignty, and territorial integrity."

The SADC force was deployed in 2023 to replace the East African Community (EAC) regional mission, which was withdrawn from the DR Congo after Kinshasa deemed it ineffective.

While the current size of the deployment in the troubled Central African country is unknown, UN estimates suggest that about 1,300 SAMIDRC troops were dispatched out of the 5,000 approved. South Africa, which leads the mission, announced early last year that it would contribute 2,900 soldiers.

DR Congo's mineral-rich eastern region has experienced decades of violence, driven by the M23 and other armed groups fighting the authorities for power and minerals such as gold and diamonds. The Congolese government has repeatedly accused neighboring Rwanda of backing the militants - claims the neighboring state denies.

Angola announced on Wednesday that it will mediate direct ceasefire talks between the rebels and officials from Kinshasa on March 18. The Congolese authorities previously refused to hold talks with the rebels, insisting they would only negotiate with Rwanda, the "aggressor."