TOKYO (Reuters) - Shares in Japan's five major trading houses rose more than 5% in early trade on Tuesday after billionaire investor Warren Buffett said his conglomerate Berkshire Hathaway ( BRK/A ) would likely increase its ownership in them.

Mitsubishi Corp ( MSBHF ) was the top performer, up 7.5%, while Mitsui & Co ( MITSF ), Sumitomo Corp ( SSUMF ), Itochu ( ITOCF ) and Marubeni ( MARUF ) each gained more than 5%.

In his annual letter to Berkshire shareholders published at the weekend, Buffett said the five trading houses agreed to "moderately relax" limits that capped Berkshire's ownership stakes below 10%.

"Over time, you will likely see Berkshire's ownership of all five increase somewhat," Buffett wrote.

Tokyo's benchmark Nikkei share average was down 1.57%. Markets were closed on Monday due to a public holiday.

Known as "sogo shosha," Japanese trading houses trade in a variety of materials, products and food - often serving as intermediaries - and provide logistical support. They are also involved in the real economy in such areas as commodities, shipping and steel.

Berkshire's investment in the companies, which began in 2019, totalled $23.5 billion at the end of 2024. It has spent $13.8 billion on its current holdings and expects $812 million of dividend income in 2025, Buffett said in the letter.