Members of Canada's opposition parties have expressed shock that two government-chartered planes that were sent to China to pick up personal protective equipment returned empty.
However, Prime Minister Justin Trudeau blames security and quarantine measures in China for the mishap.
One plane was chartered by the federal government and the other by an unnamed province.
Trudeau told reporters there are strict rules at the Shanghai Airport.
"There are severe restrictions on the ground in China in terms of how long a plane can actually stay in their airport, whether it is full or not," he explained. "At the same time, supply lines to the airport are difficult and interrupted by checkpoints and quarantine measures."
Trudeau said, for the most part, Canada has been able to negotiate those challenges, "but these two airplanes were forced to take off empty."
Canada has received millions of pieces of personal protective equipment from China, which is also sending supplies to some U.S. states. Trudeau said more would arrive in the coming days and weeks.
"It's always a challenge to get the PPE into Canada at a time when the global market is very, very competitive," he said. "But, we have managed so far."
At the same time, Canada's capacity to make its own personal protective equipment continues to ramp up.