GOMA (Reuters) -

The Democratic Republic of Congo on Thursday lifted a five-month mining ban in the east of the country but pending U.S. legislation concerning "conflict minerals" is still likely to make sourcing hi-tech metals from the region difficult.

The DRC last week said that on March 10 it would lift the ban, which it had imposed last September to curb funding to armed groups in the volatile eastern provinces of North Kivu, South Kivu and Maniema.

Industry experts say the ban was widely flouted by armed groups and will now be overtaken by U.S. legislation that is aimed at strengthening accountability in resource-rich countries.

The U.S. "conflict minerals" bill due to come into force in April will require companies to prove that minerals such as tin ore cassiterite, tantalum and coltan, extracted from the Democratic Republic of Congo and its nine neighbours, are not linked to conflict.

John Kanyoni, head of the local mineral exporters group, expressed concern that the U.S. law combined with tougher industry standards to fight conflict minerals could mean a de facto embargo on minerals from the region.

"Under the current system it is impossible for exporters to prove their minerals are conflict-free, meaning U.S. buyers will refuse to do business," he warned.

Kanyoni said the region was at least two years away from having an effective traceability and certification process in place and exclusion from trade would mean thousands of small-scale, independent miners risk losing their livelihoods.

"We have made it very clear to President (Joseph) Kabila that after April 1, we will not be able to sell our produce abroad," he said, adding that they were asking for an extension of the deadline before the new regulations are implemented.

Dieudonne-Louis Tambwe, deputy technical co-cordinator at the DRC Ministry of Mines, said the government would provide mining services and regulators would be on site. There would also be secure centres where diggers could sell their products.

"This is an answer to what the Americans are doing with the legislation. We provide documentation so that whatever products have gone through that scheme are certified," he told Reuters in an interview on the sidelines of a conference in Istanbul.

"The solution will not be easy but it would be to transform artisanal mines into more regulated small-scale mining (operations)."

TIN CHALLENGE

International tin lobby group ITRI said in a statement resumption of mining posed challenges to the tin industry because a planned project to identify minerals from the region in compliance with the U.S. law was not in place yet, with about two to three years needed to implement any programme.

ITRI said Malaysia Smelting Corporation, the world's third-largest tin producer and major supplier to the Asian market, will no longer be able to purchase minerals from the region where it gets about 15-20 percent of its supplies.

"It is not the wish of the tin industry to pull out of the central African region...but under the prevailing circumstances there may be no option," the statement said.

Some firms such as Nokia are among several end-users that have banned the use of tin, tantalum and tungsten sourced from "illegal mines" in Congo in their products.

(Writing by Bate Felix; additional reporting by Ayla Jean Yackly; editing by Mark John and Jason Neely)

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