UPDATE 1-Japan's Mitsui OSK to build 53 iron ore carriers

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HONG KONG, May 14 (Reuters) - Mitsui O.S.K. Lines Ltd, which is headquartered in Tokyo, said on Wednesday it planned to build 53 new iron ore carriers to meet rising demand.

The company said in a statement the total included four vessels that could haul 300,000 tonnes, two for 250,000 tonnes, seven to haul 230,000 tonnes and one for 200,000 tonnes.

An official from Mitsui said of the 53 orders, 20 were new and that the company was spending 160 billion yen ($1.52 billion) to construct the 20 ships. The company would add about 10 ships per year between 2008 and 2014.

"Worldwide demand for iron and steel is expected to show stable growth, with countries such as China continuing to produce more crude steel," the company said in a statement.

"Increased steel production will naturally boost demand for efficient, reliable transport of raw materials."

The Mitsui O.S.K. official also said the company had already concluded mid-term or long-term contracts for about 40 percent of the ships with mainly steel mills in Japan, China and elsewhere.

The company operated 125 vessels for iron ore as of end-March, including cape-sized and panamax-sized ships. The number would reach 160 by end-March, 2014, including about 135 cape-sized vessels and about 25-panamax sized ships.

Helped by surging iron ore demand from China, freight rates for dry bulk cargoes, including iron ore, coal or grains, have rebounded strongly following a setback late last year.