HNA Group cleared Hainan Airlines’ fuel bill to China National Aviation Fuel Group (CNAF) of $475 million (3 billion yuan), Reuters reports. The conglomerate’s subsidiary has been amassing the bill since it started skipping its payments some 7 months ago, back in autumn of 2017, according to anonymous source.

“The bill was sorted out after CNAF’s communications with the senior management of HNA Group,” one of the sources said to Reuters. Usually CNAF, which has near aviation fuel monopoly in China, gives customers one month credit period, however, it has continued to supply fuel to the HNA owned airlines despite the debt, since discontinuation would result in hundreds of grounded flights affecting passengers.

According to an inside sources, HNA had offered various solutions to settle the jet fuel bill, including the transfer of stakes in joint venture firms and real estate assets. Nonetheless CNAF preferred cash since  the transfer of stakes HNA offered would take much longer to materialize.

CNAF services 215 airports in China and 46 airports internationally and has a near monopoly on jet-fuel distribution in China, and South China Morning Post reported that the conglomerate’s airline has been missing its payments since October, 2017.

HNA has been having liquidity concerns since its $50 billion spending spree back in 2016. As a result China’s conglomerate came under scrutiny from China’s government over the stability of its financial system. China’s government is also cracking down on other private conglomerates including Dalian Wanda Group, Anbang Insurance and Fosum International.

The Chinese government stepped up the financial operations supervision of the HNA Group in autumn 2017. Its multi-billion leverage-based spending on overseas companies, sourced from domestic funds, has raised the government’s concerns about risk accumulation. For this reason, in October 2017 the company, and all its subsidiaries were banned from receiving funds from its insurance arm Bohai Life Insurance