Shanghai (AFP) - Chinese cinema-goers now have to sit through a short clip promoting "core socialist values" and President Xi Jinping's "Chinese dream" political credo before the show starts -- and some aren't happy about it.

Authorities enlisted action star Jackie Chan and domestic film idols as part of the public-service adverts, which have been ordered shown at cinemas in China since July 1 and last a few minutes apiece, state media said.

Four videos were made under the title series "The glory and the dream -- our Chinese dream", borrowing from Xi's vision of a revitalised China, and were an initiative of the State Administration of Press, Publication, Radio, Film and Television, said the official Beijing Youth Daily.

"The purpose is to help people better understand and accept the (ruling communist) party's principles and policies," it added.

The state-aligned Global Times quoted one of the videos as saying: "No matter what you do, as long as you respect the country, our society, our nation and our family, you are helping us to realise the Chinese dream."

The newspaper said Beijing cinemas were required to play one of the short videos before screenings, but theatres in other parts of the country also confirmed to AFP that they too had been showing the clip, suggesting the edict is country-wide.

"Many came late for the movie just to avoid the short video and others complained about the video after watching the movie," the Global Times quoted one cinema employee as saying.

Users on Weibo, China's Twitter-like social media platform, expressed mixed feelings.

"Had planned on going to the cinema but heard there is now a China dream trailer at the beginning, forget it," wrote one.

But another, named Good Netizen from Henan, wrote: "Three generations of film stars spreading positive energy in society. They expressed the aspirations of a Chinese person, every ordinary Chinese person's Chinese dream."

Since taking office in 2013, Xi has consolidated control to become one of China's most powerful leaders in decades, exalting the Communist Party and cracking down on its critics.