A court-appointed administrator for Democratic Republic of Congo’s Tenke Fungurume Mining SA copper and cobalt project says he’s blocked new exports from the mine until its shareholders agree on a new sales contract. 

State-owned Gecamines, which owns 20% of the venture, says it must sign a contract with China’s CMOC Group Ltd., the majority owner, in order for Tenke to export minerals. The partners, who are in a separate dispute over royalties, haven’t agreed to such a contract for this year, according to the administrator, Sage Ngoie. 

On Friday, a CMOC spokesman said nothing had changed at the mine. The spokesman didn’t respond to a message for comment on Sunday. 

“CMOC’s management is completely opaque, where they know everything and Gecamines knows nothing,” Ngoie’s office said in a message on Thursday, adding that the mine’s output is being sold to a CMOC unit “at a price that Gecamines doesn’t know.”

Tenke is one of the world’s biggest cobalt mines, accounting for about 14% of global production in 2021, according to calculations by Bloomberg using figures from Darton Commodities Ltd. It’s also a major copper producer. 

Read more: China Moly Wants Third-Party to Resolve Congo Mine Dispute 

With new exports blocked, “only those for which TFM had already prepaid before the decision of the provisional administrator are allowed, and should run through end of next week,” Ngoie’s office said. 

Reuters reported Sunday that a CMOC unit told companies that transport Tenke’s minerals to halt exports until at least July 24.

If the blockage takes full effect it will represent another escalation in a fight by Congo and Gecamines to get CMOC to pay more money for one of the African country’s key resources. 

Gecamines says that CMOC has been lying about its mineral reserves and owes the company $7.6 billion in royalties and interest. The state miner sued in 2021 to have a temporary administrator appointed to run the company while the two partners worked out their differences. Ngoie took over Tenke last month with the blessing of Gecamines, but CMOC has blocked him from entering the mining site.

CMOC has completely rejected Ngoie’s management. Deo Bukayafwa of MBM Conseil, a lawyer for Tenke’s management under CMOC, didn’t respond to a message requesting comment.