Berkshire Hathaway CEO Greg Abel stated that rising Japanese bond yields are not currently impacting the major trading houses in which the holding company has stakes. Speaking on CNBC's "Squawk Box" on Wednesday, Abel noted that while Japan's 10-year bond yield hit a 30-year high this week, it remains relatively modest compared to global yields. He added that Berkshire has received permission to increase its stakes in five major Japanese trading houses (Itochu, Marubeni, Mitsubishi, Mitsui, and Sumitomo) to over 10%.