Canada’s foreign affairs ministry has said it “strongly condemns” the execution of several of the country’s citizens in China this year, highlighting sustained tensions between the two countries.

Global Affairs Canada confirmed on Wednesday that an unspecified number of citizens were executed earlier this year. The revelations were first reported by the Globe and Mail.

“Canada strongly condemns China’s use of the death penalty, which is irreversible and inconsistent with basic human dignity,” a GAC spokesperson, Charlotte MacLeod, said in a statement to the Guardian. “Canada repeatedly called for clemency for these individuals at the senior-most levels and remains steadfast in its opposition to the use of the death penalty in all cases, everywhere.”

McLeod said Canada was providing consular assistance to the victims’ families and asked media “respect the family’s privacy during this difficult time”.

China’s embassy in Canada said in a statement it is a “rule of law” nation and that anyone convicted of breaking laws “must be held accountable”.

“Drug-related crime is a severe crime recognized worldwide as extremely harmful to the society, and will be faced with severe penalties in all countries. China always imposes severe penalties on drug-related crimes and maintains a ‘zero tolerance’ attitude towards the drug problem,” the embassy said, adding it had “solid and sufficient” evidence in all the cases in which prisoners were executed.

“The Chinese judicial authorities have handled the cases in strict accordance with the law, and have fully guaranteed the rights and interests of the Canadian nationals concerned.”

China has a conviction rate of more than 99%, a result that has elicited skepticism and criticism from human rights groups over the years.

The embassy called on Canada to “respect the rule of law and China’s judicial sovereignty” and to “stop making irresponsible remarks” in order to improve relationship between to the two countries.

Relations between the two countries hit a low point between 2018 and 2022, after the prominent Huawei telecoms executive Meng Wanzhou was arrested in Vancouver at the request of US authorities.

Her detention in Canada prompted China to quickly detain and charge two Canadians living in the country, Michael Kovrig and Michael Spavor, eventually charing the pair with espionage.

But the upgrading of charges against a Canadian in prison further cemented views in Canada that China was engaged in “hostage diplomacy”.

In 2014, the Canadian citizen Robert Schellenberg was accused of attempting to smuggle 225kg of methamphetamine to Australia. He has maintained his innocence, but in December 2018 he was sentenced to 15 years. That charge was upgraded to execution in 2019, during the fervour of China’s diplomatic spat with Canada. At the time, Canada issued a travel warning to its citizens going to China.

MacLeod confirmed on Wednesday that Schellenberg was still detained and said the federal government “continues to advocate for clemency”.