BEIJING, CHINA - AUGUST 31: Chinese President Xi Jinping (R) shakes hands with Canadian Premier Justin Trudeau ahead of their meeting at the Diaoyutai State Guesthouse in Beijing, China, 31 August 2016.

China is not putting pressure on Canada by sentencing a Canadian to death for drug smuggling, and any suggestion it was doing so showed "rude contempt" of China's law, its state media said.

Relations between China and Canada have been severely strained since early December when Canadian police arrested Meng Wanzhou, chief financial officer of Chinese telecommunications giant Huawei Technologies, on a U.S. extradition warrant.

China subsequently detained two Canadians on suspicion of endangering state security, but it has not linked their arrests to Meng's case.

On Monday, a Chinese court handed down the death penalty to another Canadian, Robert Lloyd Schellenberg, for smuggling 222 kg of methamphetamine, in a retrial of his case after he had appealed a 15-year prison sentence.

Canadian Prime Minister Justin Trudeau said it was of "extreme concern" that China had chosen to "arbitrarily apply" the death penalty.

China has not linked Schellenberg's sentence to Meng's case and the nationalist Global Times tabloid said in an editorial late on Monday that the idea that China was putting pressure on Canada with the sentence was "unreasonable speculation" and showed "rude contempt toward Chinese law".

"Public opinion in Canada has claimed recently that China is 'politicizing' Schellenberg's case, but what Canada is doing is actually politicizing law," the Global Times said.

"Whatever Canada does, it is the rule of law, but whatever China does is not. Canadian elites are feeling so righteous with this double standard, and it is time for them to wake up from such cultural and value narcissism," the paper said.

Drug smuggling is routinely punished severely in China, and foreigners convicted of drug crimes have been executed before, including a Briton in 2009.

Schellenberg's lawyer said on Monday he would appeal.

International rights groups condemned the sentence with some saying it was too severe and suggesting it may have been politically motivated.

"China is going to face lots of questions about why this particular person, of this particular nationality, had to be retried at this particular time," Human Rights Watch's Washington-based China director Sophie Richardson told Reuters.

Though Schellenberg was arrested in 2014, state media has played up coverage of his case following the deterioration in China-Canada relations.

In an unusual move, the court invited media to cover the retrial, and state television aired an unusually long five-minute segment on the proceedings.

The Global Times said the sentence would convey a message to the West that "drug smuggling faces higher risks in China".

"The trial will also send the message that China won't yield to outside pressure in implementing its law," it said.

The other two Canadians in detention are Michael Kovrig, a diplomat on unpaid leave from the embassy in Beijing, and Michael Spavor, a consultant.