A weaker yen benefits Mitsui O.S.K. Lines because much of the Japanese shipping giant's revenue is earned in U.S. dollars, Chairman Takeshi Hashimoto told CNBC. He said sharp currency swings risk creating a "confused situation" in financial and global markets, adding that a range of 150 to 155 yen per dollar would be "comfortable." Hashimoto also said it is "almost impossible" for the company to resume normal services through the Strait of Hormuz for now.