Chinese conglomerate Suning, which holds a 68.5% stake in Inter Milan, has to hand back roughly 375 million euros ($408 million) to Oaktree, a U.S.-based investment fund, by the beginning of next week.

"We have been making every attempt with our partner to find an amicable resolution, including multiple paths for Oaktree to achieve a full and immediate financial return," said Inter Milan Chairman Steven Zhang in a letter to supporters published on the club's website.

"Unfortunately, our efforts to date have been exasperated by legal threats, and a lack of meaningful engagement from Oaktree. Not only has this been deeply frustrating and disappointing, such behaviour now poses potential risks to the Club that could seriously jeopardize its stability," he said.

He gave no further detail of the content of the discussions.

Oaktree declined to comment.

In 2021 Suning secured an emergency deal to get a three-year financing package from Oaktree to help Inter Milan weather the COVID-19 pandemic.

Granted to the Luxembourg-based vehicle through which Suning controls Inter, the loan was initially worth 275 million euros and carried an interest rate in the region of 11%.

It was guaranteed by Suning's stake in Inter Milan under a scheme which gave Oaktree the potential right to take control of the club in case of a default.

Suning took control of Inter Milan in 2016, in one of the highest profile forays of a Chinese firm into European soccer.

Since then, Chinese authorities have imposed curbs over overseas spending in sport and Suning has been hit by the COVID-19 downturn.

Founded in 1908, Inter Milan are among the most storied clubs in Italian soccer and are home of top players like Lautaro Martinez and Nicolo Barella. Last month they secured their 20th Serie A league title and the second under Suning's ownership.

Inter Milan made an annual loss of 86 million euros in the 2022-2023 fiscal year and its total debts stood at 807 million euros.