"We strongly condemn the executions that did happen against Canadians in China," Joly told reporters in Ottawa.

She said she was unable to discuss details of the case due to privacy requests from the affected families.

China defended the executions in a statement sent to the Globe and Mail newspaper, which indicated the Canadians had been convicted over drug offenses.

"Drug-related crime is a severe crime recognized worldwide as extremely harmful to the society," the embassy statement sent to the Globe said.

"China always imposes severe penalties on drug-related crimes and maintains a 'zero tolerance' attitude towards the drug problem."

Joly said that she and former prime minister Justin Trudeau, who left office last week, had asked China for leniency.

China classifies death penalty statistics as a state secret, though rights groups including Amnesty International believe thousands of people are executed in the country every year.

Relations between Beijing and Ottawa have been tense in recent years.

The arrest of a senior Chinese telecom executive on a US warrant in Vancouver in December 2018 and Beijing's retaliatory detention of two Canadians on espionage charges plunged relations into a deep freeze.

Ties were strained further over allegations of Chinese interference in Canadian elections in 2019 and 2021, charges Beijing has denied.

Joly in 2023 expelled a Chinese diplomat accused of targeting a Canadian opposition lawmaker who has been a vocal critic of the ruling Communist Party in Beijing, as well as his family.

Ottawa also has criticized a security crackdown in Hong Kong and China's treatment of its Uyghur Muslim minority.