Rescue workers in Zambia have pulled out the first survivor of a 1 December landslide that inundated a open-pit copper mine and trapped at least 25 people who were working there without a permit, the disaster management unit said on Wednesday.

The rescue team also retrieved one body which had yet to be identified, the Disaster Management and Mitigation Unit said in a statement posted on Facebook.

"A 49-year-old man has been rescued from the collapsed mine slug dump site in Chingola after being trapped with several other miners," it said, adding that he was being treated in hospital.

Zambia's president Hakainde Hichilema said on Tuesday he was still hopeful that the trapped miners were still alive, as rescue efforts continued.

The miners at Seseli Mine in Chingola, about 400km northwest of Lusaka, were trapped in three locations and heavy rains had flooded the pit, the government said.

The mine was previously owned by Vedanta's Konkola Copper Mines (KCM) but is now in the hands of a local company that is yet to start mining operations as it awaits safety and environmental approvals.

It was still not clear how many miners had been trapped but Mines Minister Paul Kabuswe said on Monday 25 families had so far come forward to claim missing relatives who were working when the accident happened.

Rescue workers, including military personnel and others from large-scale mining companies, were being cautious due to soft ground, slowing down the operation.