Berkshire Hathaway, through its wholly owned unit National Indemnity Company, has raised its stake in Japan's Mitsubishi Corp and Mitsui & Co., the companies said Thursday.

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Berkshire raised its stake in Mitsubishi to 10.23% from 9.74% previously, the company said in a market disclosure. A Mitsui official confirmed Berkshire had raised its stake, but declined to give a percentage.

Its prior stake in Mitsui was 9.82%.

Berkshire previously raised its holdings in five Japanese trading houses, including Mitsubishi and Mitsui, in March.

Shares in Mitsubishi rose 1.85% and Mitsui was up 1.23% on Thursday, while the benchmark Nikkei gained 0.73%.

Sumitomo Corp rose 1.1%, Itochu increased 1.15% and Marubeni gained 1.17%.