Great American Insurance Co. needs to pay more if it wants to buy out Richfield specialty insurer National Interstate Corp.

National Interstate’s special committee of its board of directors unanimously rejected a $30.75 per share verbal proposal from Great American, the insurer announced Wednesday.

Great American is a wholly-owned subsidiary of Cincinnati-based American Financial Group Inc., which in turn is National Interstate’s majority shareholder. American Financial wants to own all of National Interstate through its Great American subsidiary.

“After careful consideration, the special committee determined that the revised offer is inadequate and is not in the best interest of the minority shareholders of the company,” National Interstate said in a press release.

The special committee will look at its options, including maintaining National Interstate as a public company and negotiating with Great American Insurance to seek a better offer, the company said.

“There can be no assurance that such discussions will result in an offer that can be supported by the special committee,” the company said in its release.

This is American Financial Group’s second attempt to buy out all of National Interstate.