China has unveiled a sophisticated new stealth fighter jet at an air show, in a show of muscle during a visit by US president Barack Obama for an Asia-Pacific summit.

President Xi Jinping has been pushing to strengthen China's 2.3 million-strong armed forces, and Chinese defence companies and the People's Liberation Army's air force have put the latest weaponry on parade at the Zhuhai air show this week.

China hopes the much-anticipated J-31 stealth aircraft, developed by the Aviation Industry Corp of China (Avic), the country's top aircraft maker, will compete with US-made hardware in export markets.

The J-31 conducted a demonstration but was not put on display afterwards although a mock-up version was on show.

An Avic spokesman declined to comment on any orders for the aircraft.

"We were told not to do any promotion for the plane," spokesman Fu Mingyao said. He did not elaborate.

There are slated to be at least two more J-31 demonstrations at the show, Avic officials said.

"Experts predict that the J-31 will make rapid inroads in the international market in the future, and will undoubtedly steal the limelight from the F-35," the ruling Communist Party's People's Daily reported on its website in August 2013.

It said the aircraft would be particularly attractive to countries that are cut off from US arms exports.

The J-31 is about the same size as the F-35, the US Department of Defence said in a report this year.

Stealth aircraft are key for China's air force to evolve from a mostly territorial air force to developing the ability to carry out both offensive and defensive operations, the Pentagon said in the report about developments in China's military.

The J-31 is China's second domestically produced stealth fighter.

Analysts say development of stealth aircraft enable China to better project its power as it takes on a more assertive stance in the East China and South China seas.

First female aerobatic fighter pilots take flight

Two female pilots have joined China's famed 'August 1st' aerobatic group performing at the air show ( AFP: Johannes Eisele )

The first women fighter pilots to join China's famed aerobatic team have also shown off their skills in J-10 jets during the event.

The pair strode to their fighter planes in lock-step with male pilots, all wearing identical green jumpsuits and sunglasses, as part of a performance by the Chinese air force's "August 1st" aerobatic group.

They are part of a group of five female fighter pilots, who have not been identified by name, flying for the team named for the date of the founding of the army.

State media has reported the women are the first to join the group.

"Female pilots have learned to fly cutting-edge fighter jets in the Chinese air force," the China Daily newspaper quoted Wang Yan'an, deputy editor of Aerospace Knowledge magazine, as saying last month.

"It means the air force has diversified its pilot pool and can recruit more female pilots," he said.

The five women all have more than 750 hours of flying time in four types of aircraft, according to state media.

The Chinese group is performing alongside the Russian air force "Knights" aerobatic team flying SU-27 fighters, as well as the United Arab Emirates air force performance team.

AFP/Reuters