NEW YORK (CNN/Money) - Warren Buffett, the chief executive of Berkshire Hathaway and one of the world's wealthiest individuals, said Wednesday the recent erosion of corporate confidence is justified due to legal, but improper, accounting methods.

In an opinion piece published in the New York Times Wednesday, Buffett singled out pension fund returns, and especially the expensing of stock options, as "the most flagrant deceptions" in corporate accounting.

Buffett issued an offer in the Times piece to CEOs who contend options are cost free: "Berkshire Hathaway will sell you insurance, carpeting or any of our other products in exchange for options identical to those you grant yourselves."

He then asked if those CEOs thought their companies would incur an expense when they handed over the options to his company and if they believed putting a value on the options was too difficult.

"If these are the opinions you honestly hold, call me collect. We can do business," he added.

The Buffett piece follows a letter from TIAA-CREF, one of the nation's largest institutional investors, sent to 1,754 companies, also requesting that corporations expense stock options.

Buffett also focused on the rate of returns companies use on pension funds, some of which go as high as 11 percent, he contended.

"The rate of return is important," he wrote. "In many cases, an upward change of a single percentage point will increase the annual earnings a company reports by more than $100 million...even as their pension assets perform miserably."

Buffett closed the Times piece by placing the blame for the current accounting situation on the Senate, saying it pushed the Financial Accounting Standards Board and Arthur Levitt, the former chairman of the Securities and Exchange Commission, into backing down from enforcing that options be expensed in 1994.

"The Senate opened to doors to an anything goes reporting system, and it should close them now," he continued. "Rather than holding hearings and fulminating, why doesn't the Senate just free the standards board by rescinding its 1994 action?"