Zambia's new government has decided to suspend all exports of copper and other metals until new guidelines are in place that would reform the country's mining industry.
Officials say the new guidelines, which aim to improve revenue collection and increase transparency in Zambia's mining sector, are expected to be implemented by October 15.
Zambia is Africa's largest producer of copper, which accounts for the majority of the country's export earnings.
Zambia's newly-elected president, Michael Sata, is a populist who campaigned to end government corruption and lessen the gap between the country's rich and poor.
Sata has criticized what he describes as exploitive foreign investors in the country's mining industry - citing, among other things, labor conditions at Chinese mining firms in Zambia. Beijing has invested heavily in Zambia's mining industry.
In the two weeks since he took office, Sata has fired the country's central bank governor, appointed a new anti-corruption chief and replaced dozens of civil servants.
Sata took office on September 23 after winning the presidential election over incumbent Rupiah Banda.
The new president has also threatened to reinstate a 25 percent windfall tax on mining revenues, which Banda's party abolished in 2009.
Some information for this report was provided by AP and AFP.