HNA Group Co., the debt-laden Chinese conglomerate on a selling spree, agreed to dispose of its last plot of land near Hong Kong's former Kai Tak airport, ending ambitions for a massive residential project in the world's most expensive property market.

A unit of Wheelock & Co. agreed to buy the land from HNA's Hong Kong International Construction Investment Management Group Co. for HK$3.9 billion ($500 million), assuming debt of HK$3 billion, according to a filing on Friday on the Hong Kong Stock Exchange.

The firm sold three other plots of land in Kai Tak for about HK$22.3 billion. Together with the last parcel, the total sale represents HNA's second-biggest disposal in a more than $20 billion selloff after the group's debts spiraled out of control.

The project, originally spanning 400,000 square feet (37,161 square meters), symbolized an era when the conglomerate was splurging on everything from over-the-top parties in French museums to some of the most expensive homes in Manhattan, even though borrowing costs were soaring.

HNA bought its land near the former airport, which has been closed two decades, from late 2016 to early 2017, paying a total of HK$27 billion. It sold the other plots of land to Henderson Land Development Co. and Wheelock. The company still owns some large historical mansions in Hong Kong.