Movement restrictions in neighbouring countries through which copper and cobalt from Congo are transported could lead to declarations of "force majeure" from miners, Mines Minister Willy Kitobo Samsoni said in a ministry analysis seen by Reuters.

Cobalt exports slumped by 15.2% in the first quarter compared to the same period last year, he said, while copper exports increased by 12.8% year-on-year. Congo is the world's biggest producer of cobalt, a metal used in batteries.

"The DRC would not be able to withstand an abrupt halt in the mining production of the flagship projects operating there if they invoked force majeure," Samsoni wrote in the memo.

Among the companies mining in Congo's southern copper belt are Glencore subsidiary Katanga Mining, China Molybdenum's Tenke Fungurume, MMG, Ivanhoe, and Chemaf.

Mining projects under development and planned for 2020-2021, like Ivanhoe's Kamoa-Kakula copper mine project, are likely to be postponed due to low prices, Samsoni predicted.

An Ivanhoe spokesman declined to comment on Friday, referring Reuters to the company's press statement of April 2 in which it said it had locked down the Kamoa-Kakula site with all key personnel on site.

That was to ensure operational continuity and minimise the impact of the epidemic on the development schedule, it said in the statement.

Shutdowns would dent government revenue at national and regional level, and deprive the mines ministry of the means to operate, Samsoni continued.

Mining companies are an important contributor to government finances through royalties paid on minerals including copper, cobalt, and gold.

(Reporting by Hereward Holland and Helen Reid; Editing by Jane Merriman)