Canadian Prime Minister Justin Trudeau (R) meets with Chinese Foreign Minister Wang Yi in Ottawa. (Chris Wattie/Reuters)

Wang Yi did not like the question.

At a news conference in Ottawa on Wednesday, Canadian journalists were granted the chance to ask the Chinese foreign minister a single query, plus a follow-up. They asked about human rights. Wang lost it.

"Your question is full of prejudice and against China and arrogance. ... I don't know where that comes from. This is totally unacceptable," Wang said, speaking through an interpreter.

"Other people don't know better than the Chinese people about the human rights condition in China, and it is the Chinese people who are in the best situation, in the best position to have a say about China's human rights situation," he said.

Wang asked the journalist whether she had ever been to China. "Do you know that China has lifted more than 600 million people out of poverty?" he asked.

"And do you know that China is now the second-largest economy in the world from a very low foundation? ... And do you know China has written protection and promotion of human rights into our constitution?"

The heart of what Wang said — that only China is equipped to understand China — is not new. The ruling Chinese Communist Party often expresses anger and frustration over what it considers the ignorance and hypocrisy of the West, particularly when it comes to human rights. They think China is targeted unfairly and willfully misunderstood.

What's surprising and revealing is that Wang let himself look rattled.

The question, which was broad, left plenty of room for Wang to articulate China's position on specific issues of domestic and foreign policy. Given the restrictive format, he could have held the floor, fending off a follow-up by sticking to his notes. Instead, he lost his cool.

The outburst is a reminder of how rarely China's top leaders face the news media. At home, their public appearances are rare and tightly scripted. At Premier Li Keqiang's annual news conference, for instance, a select group of local and foreign journalists are "invited" to ask screened questions on live TV.

During President Obama's November 2014 visit to China, a journalist from the New York Times surprised President Xi Jinping with a question about journalists being denied visas based on their coverage. Xi paused, gazed across the room, then took a question from state media. Later, he returned to the Times reporter, awkwardly comparing journalists to broken-down cars.

Xi, unlike Wang, managed to look composed, but his words conveyed frustration and unease. "When a car breaks down on the road, perhaps we need to get off the car and to see where the problem lies," he said.

"And when a certain issue is raised as a problem, there must be a reason. In Chinese, we have a saying: The party which has created a problem should be the one to help resolve it."