JOHANNESBURG/ LONDON (Reuters) -China's CMOC Group, the world's top cobalt mining company, called on Democratic Republic of Congo last week to lift a ban on exports of the battery metal, which is currently due to expire next month, three sources told Reuters.

Congo, the world's leading cobalt producing country, imposed the four-month ban in February in an attempt to curb surpluses as cobalt prices touched nine-year lows around $10 a lb, or $22,000 a metric ton. 

CMOC's Vice President Kenny Ives told delegates at a closed-door session during an industry meeting in Singapore that Congo should lift the export curbs on the metal, an important ingredient in electric vehicle batteries, the sources said.

Congo's Mines Minister Kizito Pakabomba was attending the session, said the sources, who heard Ives' remarks.

Congo has kept the market guessing on its next steps when the ban ends on June 22. The government could extend the suspension and could also look at export quotas for the future, sources told Reuters in February.

Ives said China's pipeline inventory was running out, and Congo needed to allow miners to freely export cobalt, said the sources, who asked to remain anonymous due to the sensitivity of the matter.

Ives argued that Congo's restrictions on cobalt exports risked accelerating automakers' switch to lithium iron phosphate (LFP) batteries that do not need cobalt. 

Some Chinese EV makers, including BYD, have already adopted LFP batteries, which are also used for utility-scale energy storage projects. 

Two of the sources said Congolese officials present at the event construed Ives' reference to LFPs as a threat. One of the sources said the comments reinforced the officials' concerns that China is seeking to depress cobalt prices in order to build up strategic stockpiles. 

Congolese officials, including Pakabomba, did not respond to emailed requests for comment or phone calls.

CMOC spokesperson Vincent Zhou declined to comment on Ives' remarks or questions regarding Congo's stockpiling fears but said that the company favours a "healthy market environment". 

Chinese electric vehicle battery maker CATL is among CMOC's largest shareholders, with a 30% stake in the miner, according to LSEG data.

CMOC expects to produce between 100,000 and 120,000 metric tons of cobalt this year - within range of last year's 114,000 tons and roughly double the 56,000 tons produced in 2023 - as it ramps up activity at its Tenke Fungurume and Kisanfu copper and cobalt mines in Congo.

GLENCORE BACKS EXPORT CURBS

At the same session in Singapore, traders from Glencore ( GLCNF ), another leading cobalt miner, said the market required a stable price before the export ban is lifted and producer countries like Congo and Indonesia needed to manage oversupply, the three sources said.    

Glencore ( GLCNF ) declined to comment.

The Glencore ( GLCNF ) traders in Singapore said the company would accept a quota system, if Congo's government chooses to implement one, the sources said. 

Chinese smelters have built up stockpiles that will last between two weeks and six months, Shirley Wang, general manager at Shanghai Metals Market, said at the Singapore conference.

Congo is currently evaluating the impact of the ban and considering proposals from mining companies and others involved in the market, one of the sources said, adding that the downside of halted exports was a loss of tax revenues for the government.

"The most likely scenario appears to be either an extension of the ban followed by the introduction of an export quota, or a direct transition to an export quota starting in late June," Benchmark Mineral Intelligence said in a recent release.

"Both scenarios are likely to provide further support to pricing."