US prominent investor Warren Buffett has written that he is looking to increase his company's holdings in Japan's five largest trading houses in his annual letter to shareholders.



The 94-year-old Buffett, one of the world's best-known investors, draws attention whenever he makes a major investment.



The Berkshire Hathaway investment firm started buying stock in Itochu, Marubeni, Mitsubishi, Mitsui and Sumitomo in 2019.



The company had agreed to keep its stake below 10 percent in each trading houses.



Buffett wrote in the letter "But, as we approached this limit, the five companies agreed to moderately relax the ceiling. Over time, you will likely see Berkshire's ownership of all five increase somewhat."



He also wrote he expected his company "will be holding this Japanese position for many decades and that Berkshire will find other ways to work productively with five companies in the future."



Buffett is concerned about US government finances, saying "Paper money can see its value evaporate if fiscal folly prevails. In some countries, this reckless practice has become habitual, and, in our country's short history, the US has come close to the edge."



He added "never forget that we need you to maintain a stable currency and that result requires both wisdom and vigilance on your part."