China's new self-developed floating production, storage and offloading (FPSO) vessel has completed the construction of its main hull structure, China National Offshore Oil Corporation (CNOOC) said on Thursday, marking a breakthrough in the country's development and manufacturing capability for ultra-large offshore oil and gas equipment.

The vessel, named Haiyang Shiyou 122, is also Asia's first cylindrical FPSO, which integrates the functions of crude oil production, storage and external transmission.