Zambia, Africa’s second largest copper producer, will increase underground mining royalties from 6% to 8% as part of a major overhaul to the industry’s tax system, Finance Minister Alexander Chikwanda said in his 2015 budget speech last Friday. Royalties for open-pit mines are now 20%, also up from 6%, Reuters reports. Chikwanda was reportedly considering scrapping corporate income tax for mines and increasing royalties instead, as it is simpler to administer. The country, which last year lost its position as Africa’s top copper miner to Congo for the first time since 1998, has been withholding $600 million in VAT refunds owed to mining firms, after companies failed to produce import certificates from destination countries, according to Infomine.

Two mining companies very involved in the Zambian mining industry, Glencore and First Quantum Minerals, have voiced strong objections. Indeed, First Quantum, considered to be Zambia’s largest foreign investor, said that the country’s decision to raise mining royalties from 2015 would discourage future endeavours and cost jobs.

First Quantum’s Zambia Government Affairs Manager, John Gladston, told Reuters that the new tax system would “inevitably” lead to fewer new jobs and dissuade entrepreneurs from investing in the country. The company has already delayed investment projects worth $1.5 billion in Zambia due to uncertainty over the fiscal regime.