The billionaire co-founder of Chinese property developer Guangzhou R&F Properties Co. Ltd., Zhang Li, is wanted in the U.S. over allegations he provided kickbacks to secure contracts in California.

Zhang, a former government official who rose to lead one of China’s largest real estate firms, was arrested on Nov. 30 by London police and is facing extradition proceedings. He is contesting his transfer to the U.S.

Judge John Zani granted bail of £15 million ($18.4 million) on Monday at Westminster Magistrates’ Court, the joint highest sum ever recorded for the U.K. courts. He’ll be confined 24 hours a day in an apartment on the 43rd floor of a London tower, monitored by security and CCTV.

The 69-year old Zhang is alleged to have “provided kickbacks and funds to co-conspirators in order to obtain the appropriate permits for a construction project,” according to a court listing. 

R&F did business in the U.S. through a domestic affiliate. Among other projects, the company was responsible for a large, multi-million-dollar mixed-use residential and commercial development project in San Francisco, the listing says. 

Zhang’s lawyer declined to comment outside court. Hong Kong-listed R&F Properties, which is providing £10 million of the bail, said on its official WeChat account that it planned to fight what it called “false allegations” that Zhang was charged with bribery “for hosting a dinner in China for a former public affairs executive in San Francisco and providing him with hotel accommodation.”

He will be housed in a 5-bedroom apartment, complete with former military operatives on guard in 12-hour shifts. The security operation will cost some £200,000 a month, the court was told. Zhang will be denied any device that connects to the internet.

The aim is to try to replicate as closely as possible the standards of a prisoner on remand, the security operations manager told the court.

Zhang founded R&F with Hong Kong native and a former trader, Li Sze Lim, and made their name by purchasing a large land parcel in suburban Guangzhou and later selling it for a big profit.

—With assistance from Foster Wong.

This article was provided by Bloomberg News.