Arcelor Mittal steel foundry. Photo: Arcelor.

Johannesburg - ArcelorMittal South Africa, a unit of the world's top steelmaker, narrowed its full-year loss on Friday helped by a weaker rand and as firmer steel prices helped offset a decline in sales.

Africa's biggest producer of steel said its diluted headline loss was 56 cents per share for the year to end-December, compared with a loss of 129 cents a year earlier.

Headline earnings are the main measure of profitability in South Africa.

The company said it expects an improved first quarter performance as international prices pick up modestly.

It also sees higher sales volumes after a seasonal slowdown in the fourth quarter.

The company said it wrote off 1.9 billion rand ($173 million) for fixed assets at the Thabazimbi iron ore mine after it gave up financial control of the mine last year following a new supply agreement with Kumba Iron Ore.

ArcelorMittal South Africa shares have gained 14 percent so far this year, compared with a 2.7 percent decline by Johannesburg's All-share index. - Reuters