FARGO, N.D. — The chairman and CEO of RDO Equipment Co. expressed an interest in paying at least $21 million to buy the third of the company he does not already own, the company said.

Ronald Offutt told the Fargo, N.D., company in a letter that if he decided to go ahead with the offer he would go directly to the company's shareholders in a tender offer.

Offutt is not asking RDO to enter into any agreement, but has asked the company's board of directors to create an independent special committee to discuss the price and terms before he proceeds.

He indicated he is considering a bid of between $5.22 and $5.66 a share, the upper end of which would offer a 31 percent premium to RDO shareholders based on the $4.32 closing price on Dec. 16 on the New York Stock Exchange before the announcement.

Offutt owns about 8.1 million shares of the company's Class A common stock, including 7.5 million shares of Class B common stock that is convertible into Class A shares.