(Adds details)
LUSAKA, May 9 (Reuters) - Vedanta Resources ' VED.L Zambia unit, Konkola Copper Mines (KCM), is disputing a bill of almost $18 million slapped on it by tax authorities after an audit, an industry source familiar with the matter, told Reuters on Wednesday.
Zambia's revenue authority concluded audits of mining companies that prompted it to hit Canadian miner First Quantum Minerals FM.TO with a tax bill of $8 billion.
A KCM company spokesman declined to comment on the matter, and officials from the Treasury and the revenue authority could not confirm the dispute and the size of the tax bill.
Several African governments, including Zambia, Tanzania and Democratic Republic of Congo, are trying to extract more revenue from their resources, unnerving investors as they hike taxes or withhold VAT refunds.
The source said some other mining companies were also disputing the tax bills but was not sure whether they would be part of a planned Wednesday meeting with the finance minister.
First Quantum said in March that Zambia's tax agency had demanded the taxes, saying they were on import duties, penalties and interest on consumables and spare parts. ZRA said on Monday it had audited all the major mining companies in Zambia and informed them of what they owed.
Other mining firms operating in Zambia, Africa's second-largest copper producer, include Glencore GLEN.L and Barrick Gold Corp ABX.TO .