About 3,000 workers at Zambia Sugar, a unit of South Africa's Illovo Sugar, have gone on strike demanding a 35 percent pay rise, the company said on Wednesday.

Zambia Sugar said in a statement that operations at its Nakambala Sugar Estate, about 130 km (80 miles) south of Lusaka, had been disrupted following the illegal strike, which started on Tuesday.

“The union has addressed workers and asked them to return to work immediately and advised that the strike action is illegal,” Zambia Sugar said.

The company said any employee who did not report to work would be deemed to have breached their employment contract and dismissed. Union officials could not immediately be reached for comment.

Zambia Sugar expects its sugar output to increase by more than 7 percent to over 400,000 tonnes in the current 2012/2013 season from last year.

Wage negotiations between Zambia Sugar and the union began in January but collapsed in May after the company said it could not meet their demands.

Zambia Sugar subsequently took the matter to court but the workers went on strike before the court could make a ruling, the company said. - Reuters