Lusaka - Workers at Barrick Gold's Lumwana mine resumed work on Tuesday after staging a one-day strike over plans by the Canadian company to pull out of copper-rich Zambia, a union official said.Mine Workers' Union of Zambia (MUZ) representative Leonard Phiri told AFP the decision to resume work follows reassurances by the government that no job loses would occur."Last night [Monday] government representatives and union officials held a meeting and later addressed the workers and assured all of us that our jobs are safe," he said."As things stand now, the situation has returned to normal. We are now working."The strike came after Barrick Gold announced it would suspend operations at Lumwana after the Zambian government increased a mineral rights levy to 20% mineral rights from 6% despite global copper prices having fallen by around a fifth over the past year.Nearly 4 000 people work at the mine.But on Monday, President Edgar Lungu promised "not allow a single mining job to be lost" and directed the ministry of mines to ensure that the site remained operational.Zambia is one of the world's largest producers of copper.Lungu, who narrowly won last month's presidential election, said his government was working to "rapidly" address concerns over the new royalties.Zambia's chamber of mines has warned the taxes could cost the country $7bn in lost output over the next five years, nearly a third of its GDP and lead to the loss of 12 000 direct jobs in the mining sector.Despite copper contributing around 70% of foreign exchange earnings, Zambia is ranked among the world's poorest countries.