The activist fund that’s become Hanjin Kal Corp.’s single largest shareholder said it proposed to buy all the South Korean company’s shares held by Delta Air Lines Inc., aiming to raise the stakes ahead of a proxy fight.

Korea Corporate Governance Improvement, which has been pushing to shake up Hanjin Kal’s management, sent a proposal to Delta in mid-March to buy the U.S. carrier’s 15% stake, the fund said in an emailed interview. But the airline hasn’t responded to the offer, it said. The stake is valued at 388 billion won ($315 million) based on Thursday’s closing prices.

“Delta would be able to raise decent cash holdings through a block deal outside the market,” KCGI said. “KCGI regards this lack of any responses from Delta as highly puzzling. KCGI urges Delta to raise a decent portion of short-term liquidity by divesting.”

Such a deal could give the fund influence over a majority stake in the company, parent to flag carrier Korean Air Lines Co., and pave the way for it to wrest control of the firm from Walter Cho, the 44-year old scion who took over from his late father as chief executive officer last year. The fund has teamed up with Cho’s older sister, who’s said her brother is unfit to serve as CEO, and is calling for Hanjin Kal to abandon dynastic rule by installing professional managers.

Delta didn’t immediately respond to an emailed query seeking comment.

The fund’s proposal comes as Cho prepares to face off against the fund and his sister at a shareholders’ meeting Friday. Cho only owns about 6.5% of Hanjin Kal shares but he counts Delta as an ally after Korean Air formed a joint venture with the American carrier in 2018. Also on his side is the country’s largest pension fund, the National Pension Service, which on Thursday said it would vote for Cho. Altogether, the scion has secured more than 40% of the votes.

On the other corner is the KCGI fund, which owns a 19% stake, and the CEO’s sister, Heather, who gained global notoriety in 2014 when she held up a flight from taking off because she was outraged at the way she was served nuts. In January, she formed an alliance with KCGI and South Korean builder Bando to replace Hanjin Kal’s management at the shareholder meeting. That alliance controls more than 42% of the company’s shares but only a 29% stake will count for Friday’s vote because the rest of the shares were built up this year.

Hanjin Kal shares fell 2.8% to 44,050 won. The stock had more than doubled earlier this year before it surrendered most of those gains amid the global selloff sparked by the coronavirus outbreak. The shares are now up 10% in 2020.