BEIJING (REUTERS) - Chinese state media released videos of foreign citizens praising the country on the eve of celebrations to mark the 70th anniversary of the People's Republic, as new research showed declining perceptions of China in many western countries.

The videos, published over the weekend ahead of a vast military parade scheduled for Oct 1, show foreign citizens, identified by country, singing patriotic ballads and praising China's culture and development.

"I love you China... I love your homegrown sugar cane, that quenches my heart like milk," sang a chorus of singers including Canadians, Germans and Americans in a video filmed in the eastern city of Nanjing.

The video was posted by state broadcaster CCTV with English subtitles on YouTube, which is blocked by authorities inside the country.

Another video showed Thai citizens praising Chinese movies, bridge engineering and traditional food with hashtags linking to the country's 70th anniversary celebrations.

The patriotic videos, designed to bolster support for the anniversary of the establishment of Communist Party-ruled China, were released as attitudes towards China in many countries have darkened amid a backlash over trade, Hong Kong and human rights.

A new report released on Monday by the US-based Pew Research Centre showed that perceptions of China have declined in the past year in countries including the United States, which is locked in a bitter trade war with Beijing.

Canada, Sweden and Australia, which have had diplomatic disputes with China, have also seen perceptions weaken.

A median of 41 per cent of respondents in 32 countries surveyed have a favourable opinion of China, compared with a median of 37 per cent with an unfavourable opinion, the survey found.

Nearly 35,000 people were surveyed.

Countries that viewed China more favourably included Russia, where 71 per cent of people polled viewed the country positively, while young people across all countries had more positive attitudes in general.

President Xi Jinping will oversee Tuesday's military celebration, which will include people from foreign countries, organisers have said.