A spokesman for Hyundai Securities said the executives wanted to accept responsibility for the firm's mediocre performance and assist in restructuring.
A Hyundai Securities official gave no reason yesterday for the impasse.
A group advocating shareholders' rights has threatened legal action if the board of Hyundai Securities sells shares at a significant discount, as it has promised to do.
The price set by the board, according to the group, is nearly half the current listed price for Hyundai Securities.
Hyundai Securities is the plum in the deal: its profit nearly tripled in the last year, to 305.2 billion won - now almost $275 million.
His resignation will be accepted at a board meeting scheduled for next Monday, Hyundai Securities said.
But later in the day, the company said that the agreement would fall apart if Hyundai Securities priced its shares at 8,940 won, or $6.80.
A.I.G. is said to have expected a share price of 7,000 won for Hyundai Securities.
Shares of Hyundai Securities fell 12 percent today.
The A.I.G. consortium, however, would maintain control of all three firms through Hyundai Securities.