A military drone said to be able to cruise for 20 hours at 50,000ft is among Chinese warplanes, missiles and other weapons technology being shown in public for the first time at the country's biggest air show.

The Chinese space programme also plans to unveil a rocket for crewed space flight capable of carrying a 25-tonne payload to lunar orbit at the 13th China International Aviation and Aerospace Exhibition in Zhuhai, in the southern Guangdong province, an official newspaper said.

The event, which runs until Sunday, was postponed from late 2020 due to the coronavirus pandemic.

The ruling Communist Party is pouring billions of dollars into developing fighter jets, stealth technology, drones and other hardware for its military wing, the People's Liberation Army, as it presses its claims over disputed seas and other territory.

Powered by two turbofan engines, the CH-6 drone can carry early warning radar, air-to-ground missiles and other weapons, according to its manufacturer, the China Academy of Aerospace Science, a subsidiary of the China Aerospace Science and Technology Corporation.

The newspaper Global Times, which is published by the ruling party, said the CH-6 is aimed at "high-end arms and dual-use markets" but gave no indication as to which governments the company might try to sell it to.

The China Academy of Launch Vehicle Technology plans to unveil a "next-generation manned carrier rocket and a heavy-lift launch vehicle", the Global Times said.

It said the 2,000-tonne, three-stage rocket would "support China's manned lunar probes."

Also at the air show, the PLA's air force planned to display a J-16D electronic warfare airplane for the first time, according to the official China News Service.

China Aerospace Science and Technology Corp displayed an array of new missiles for the first time.

The China Academy of Aerospace Science also plans to show a mini-attack drone, the CH-817.

It said the 800-gramme (28-ounce) drone can be used by soldiers or can be released from a bigger drone.