Mitsui O.S.K. Lines Ltd. and Navix Line, Ltd., the country's second- and fourth-largest maritime transport companies, will merge as of April 1, becoming one of the biggest maritime carriers in the world, top executives of the two companies announced on Friday.

"We can mutually complement each other through this merger by strengthening our management base and making the best use of our corporate resources," said Masaharu Ikuta, president of Mitsui O.S.K. Lines.

In the merger, 3 1/2 shares in Navix Line will be exchanged for one share of Mitsui O.S.K. Lines. The new company will have the name of Mitsui O.S.K. Lines, Ltd. and Ikuta is expected to become president of the new firm.

As of March 1998, Mitsui O.S.K. Lines had 360 vessels and about 1,132 employees, while Navix Line had 152 vessels and 601 employees.

The new company will have capital of 64.9 billion yen. The total sales of the two carriers at the end of March amounted to 709.7 billion yen, including 571.7 billion yen at Mitsui O.S.K. Lines.

The planned merger is expected to strengthen transport services for energy and raw materials such as oil and liquefied natural gas because Mitsui O.S.K. Lines, which offers comprehensive services, will effectively take over Navix Line, which is strong in transporting those items.

Navix Line shifted its focus to transporting energy and raw materials after it virtually withdrew from the container service sector in 1991.

Energy-scarce Japan relies on imports for most of its energy and raw materials supplies, creating a stable demand for the transport of such cargo.

In addition, Japanese carriers are conventionally strong in the sector because transporting energy and raw materials requires high skills and special vessels, in contrast with container cargo service.