(Adds comment form BHP Billiton (LON:BLT))
March 31 (Reuters) - Guinea and Burkina Faso plan to take back hundreds of unused mining permits for re-auction, ministers said this week, as governments try to reignite interest in the sector.
Permits awarded in recent years that are not being used for exploration or production should be made available to other companies, the two West African countries said in separate statements.
Both countries' mining ministries said the changes were brought about to clean up their outdated land registries. But they also come as resource-rich African countries struggle to entice investment due to a global slump in commodities prices.
In Guinea, Africa's largest bauxite producer, 142 of 2,500 permits covering bauxite, gold, diamond and uranium prospects were recently made void, the Guinean minister of mines Abdoulaye Magassouba said on Wednesday.
The companies that held the licenses had been informed, one source in the ministry said.
The permits included some for bauxite blocks previously held by BHP Billiton BHP.AX in Boffa in the west of the country, the minister said.
BHP Billiton said it exited its aluminium business through a spin-off of part of its operations last year that created a new company, South32 S32.AX , and no longer holds aluminium assets.
"This is a normal process when we see that licensees do not put them to use after a time defined by the law. This also helps give way to other companies," Magassouba said.
In gold-producing Burkina Faso, the ministry of mines has published a list of 356 permits that have become available to lease, some dating back years.
"To be able to update the register, it is important that we have a clean register from the beginning with valid research and exploitation permits," Alpha Omar Dissa, Burkina Faso's minister of mines and energy, said on Thursday.