Chinese President Xi Jinping scolded Canadian Prime Minister Justin Trudeau in an on-camera dressing down at the G20 summit, an unusual public spat that could further complicate strained relations between the countries.

Video recorded by reporters at the Bali summit for world leaders on Wednesday showed Xi appearing to upbraid Trudeau after details of talks between the two leaders were leaked to the media.

Trudeau had on Tuesday raised with Xi the issue of what he called Chinese "interference" with Canadian citizens after Ottawa in recent weeks accused Beijing of meddling with its democratic and judicial systems.

In the one-minute clip captured on the sidelines of the Indonesian summit, Xi tells Trudeau through an interpreter: "Everything we discussed has been leaked to the papers. That is not appropriate." He adds: "And that's not the way (our discussion) was conducted, was it?" China's foreign ministry on Thursday sought to play down the footage, saying it showed a "normal" conversation between the two leaders and "should not be interpreted as Xi Jinping criticising or blaming anyone".

"The reasons for the difficulties in China-Canada relations in recent years are very clear," spokeswoman Mao Ning said at a regular press briefing.

"The fault does not lie with the Chinese side." /- 'Create conditions' -/In the footage, Xi tells Trudeau: "If there is sincerity, we can have conversations based on an attitude of mutual respect. If not, the results will be unpredictable." Xi then appears to try to walk past the Canadian leader, who replies: "In Canada, we believe in free, open and frank dialogue, and that is what we will continue to have.

"We will continue to look to work constructively together, but there will be things we disagree on." Raising his hands, Xi cuts him off, saying: "Create the conditions. Create the conditions." He then broadens his smile, barely looking at Trudeau as he shakes his hand and leaves his counterpart to make his way out of the room.

It is not clear when, if ever, Xi becomes aware that the conversation is being filmed.

The foreign ministry spokeswoman denied that Xi's words "if not" amounted to a threat, saying "both sides are expressing their respective positions".

"Frank dialogue is not a problem for China, but we hope (it) will be built on a basis of equal and mutual respect instead of condescending criticism," she said.

/- 'Awkward position' -/It was "extremely rare" for Chinese leaders to show their displeasure in such an "off-the-cuff" way, said Chong Ja Ian, an associate professor of political science at the National University of Singapore.

Xi's remarks suggest he feels "he can pressure Trudeau with few repercussions, if any", Chong told AFP, adding that the Chinese leader's "high degree of confidence" might indicate "he does not take either Trudeau or Canada that seriously as interlocutors".

In contrast, "Xi's body language with (US President) Biden just a few days before... seemed more cordial", he said.

The Chinese leader's tone was akin to "a great power speaking to a less-great power", said Van Jackson, senior lecturer in international relations at Victoria University of Wellington, New Zealand.

"Xi's language and body posture was not at all unusual for government officials who are on less than friendly terms -- in private," Jackson told AFP.

Tensions between China and the United States put Canada in an "especially awkward position", he said, adding that Ottawa's "embeddedness in the network of Anglo-Saxon, intelligence-sharing democracies all but ensures it will draw China's ire more and more as time passes".

Xi's Tuesday meeting with Trudeau was the first face-to-face dialogue between the two leaders since 2019.

It came after the Chinese leader last month broke longstanding political precedent to take a third term in power and stack top government positions with his personal allies.

Canadian federal police said last week they were investigating so-called police stations set up illegally by Beijing in the North American country.

Trudeau also said last week China was playing "aggressive games" after Canadian broadcaster Global News reported on a "clandestine network" of federal election candidates funded by Beijing.

Relations between the two countries plunged into the deep freeze when Canadian authorities arrested Huawei executive Meng Wanzhou in 2018 for allegedly flouting US sanctions on Iran.

Beijing later detained two Canadian citizens in China, Michael Spavor and Michael Kovrig, in what critics called a tit-for-tat response.

Meng and the two Canadians were released last year after lengthy negotiations.