French nuclear company Areva's local business in Niger denounced a 72-hour strike at its COMINAK uranium mine as a violation of a previous agreement over bonuses.
Workers launched the strike on Monday, demanding the full payment of bonuses they say they are owed for reaching financial targets last year, according to a union leader who said the company had released 70 percent of the amount.
However, COMINAK management said it had agreed with the workers to pay 70 percent initially, with the remainder to be paid after shareholders approved company results at a meeting in June.
"COMINAK management deplores the unions' position," it said in a statement on Tuesday released via Areva Mines Niger. "This is in violation of the negotiated agreements."
The statement said the bonuses had already been increased by 50 percent over the previous year as part of negotiations.
An official with SYNAMIN, one of two unions along with SYNTRAMIN which called for the strike, said on Monday the workers would evaluate the company's response after three days with a view to possibly extending the stoppage.
Located in northwestern Niger, COMINAK produced 1,607 tonnes of uranium in 2015.
AREVA owns 34 percent of COMINAK with the state of Niger 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.
(Reporting by Boureima Balima; Writing by Joe Bavier)