Warren Buffett says two potential successors earned roughly $18 million each last year managing Berkshire Hathaway's dozens of operating companies.

Buffett appeared on CNBC Monday after releasing his annual letter to shareholders over the weekend.

Buffett says Greg Abel and Ajit Jain have both done a great job since they joined Berkshire's board in early 2018. Jain oversees the conglomerate's insurance businesses while Abel oversees non-insurance business operations.

He says one of the two longtime Berkshire executives will likely become CEO eventually, but the 88-year-old Buffett has no plans to retire.

Buffett also says the two investment managers that Berkshire hired several years ago have done well, though their investments have trailed the S&P 500 a bit since they joined Berkshire. He did say both have outperformed his own investments.