Canada is advising citizens to "exercise a high degree of caution" if they travel to China amid a deepening diplomatic dispute between the two nations.
Hours later, in response, China issued its own advisory to its citizens travelling to Canada.
The updated risk assessment from Ottawa came soon after a Chinese court sentenced a Canadian man, Robert Lloyd Schellenberg, to death for what China said was his role in a drug smuggling scheme. Schellenberg initially received a 15-year prison term, which he appealed as too harsh.
The risk update also comes after Chinese authorities reportedly detained at least 13 Canadians since Canada arrested Huawei chief financial officer Meng Wanzhou at Vancouver's airport on December 1 at the request of the US. Most of the Canadians detained in China have been released, according to Canadian media reports. Ms Meng was released on bail on December 11 and is reportedly living in a luxury home in Vancouver as she awaits the outcome of her extradition hearings.
Canada has four levels of risk assessment and the new one for China is the second level:
"There are identifiable safety and security concerns or the safety and security situation could change with little notice. You should exercise a high degree of caution at all times, monitor local media and follow the instructions of local authorities."
The third level of risk would see Global Affairs Canada advising Canadians to "avoid all non-essential travel" to China.
"There are specific safety and security concerns that could put you at risk. You should reconsider your need to travel to the country, territory or region. If you are already in the country, territory or region, you should reconsider whether or not you really need to be there. If not, you should consider leaving while it is still safe to do so. It is up to you to decide what 'non-essential travel' means, based on family or business requirements, knowledge of or familiarity with a country, territory or region, and other factors."
The highest level advises Canadians to "avoid all travel" to a country or area of the world.
"There is an extreme risk to your personal safety and security. You should not travel to this country, territory or region. If you are already in the country, territory or region, you should consider leaving if it is safe to do so."
A spokesperson for Global Affairs Canada couldn't immediately be reached for comment.
Overnight, Chinese Foreign Ministry spokeswoman Hua Chunying, speaking at a regular news briefing in Beijing, expressed "strong dissatisfaction" with comments made by Canadian Prime Minister Justin Trudeau on news of the death sentence for Schellenberg.