Workers at French nuclear group Areva's COMINAK uranium mine in Niger launched a 72-hour strike on Monday claiming they had not received the full payment of bonuses for reaching financial targets last year, two unions said.
He said the company had paid 70 percent of their annual bonuses despite what he said was an agreement to pay the full amount. He said the workers would evaluate the company's response after three days and could then decide to extend the strike.
The SYNTRAMIN union also backed the work stoppage.
Officials at the mine and Areva were not immediately available for comment.
Located in northwestern Niger, COMINAK produced 1,607 tonnes of uranium in 2015.
AREVA owns 34 percent of COMINAK with the Nigerien state holding 31 percent. Japan's Overseas Uranium Resources Development Company Ltd holds 25 percent of the mine and Spain's Empresa Nacional des Uranio owns the remaining 10 percent.