China's Long March 5B carrier rocket is expected to set off on its maiden flight in the first half of 2020, said Zhou Jianping, chief designer of the nation's manned space program.

Zhou made the remarks on Tuesday during an event celebrating the 2019 China Space Day, Science and Technology Daily reported.

The space station primarily consists of Core Capsule, Experiment Capsule I and Experiment Capsule II, each weighing 20 tons, said Zhou.

According to the plan, the space station program will be implemented in three phases: key technologies validation, construction and operation, Zhou added.

Six flight missions including the maiden flight of the Long March-5B rocket have been scheduled to validate key technologies, and six launches for the construction phase have also been listed.

When the space station is in orbit, Shenzhou manned spaceships will transfer astronauts, and Tianzhou cargo spaceships will deliver supplies.