Canadians Michael Kovrig and Michael Spavor were detained in China days after Meng Wanzhou was arrested at the request of US authorities.
Mr Trudeau says that China is “using arbitrary detention as a tool to achieve political goals”.
Ms Meng’s detention has badly strained relations between Ottawa and Beijing.
Mr Trudeau told the Toronto Star editorial board that the detention and arrest of the pair, who are facing espionage charges, was “unacceptable” to Canada.
His government has sought the support of Western allies in securing the release of the two men. Their arrests have widely been viewed as tit for tat to pressure Canada to release Ms Meng, the chief financial officer of the Chinese telecoms giant.
Speaking on Thursday, he told the newspaper that “using arbitrary detention as a tool to achieve political goals – international or domestic – is something that is of concern not just to Canada but to all our allies who have been highlighting that this is not acceptable behaviour in the international community because they are all worried about China engaging in the same kinds of pressure tactics with them.”
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Mr Trudeau said Canada had to find a way to engage constructively with the Asian economic powerhouse.
But he cautioned that “we also have to be clear eyed about it – that China plays by a very different set of rules and principles than we do in the West”.
He said that Canada would continue to “make those points clearly and forcefully”, but “won’t look to escalate” the diplomatic spat between the two countries.
Ms Meng, 47, was arrested in Canada in December. The US wants her extradited to be tried on charges of fraud linked to alleged violation of sanctions on Iran.
Both she and Huawei deny those allegations.
Ms Meng is currently living under house arrest in Vancouver, Canada, and is waging a legal battle against extradition.
The prime minister’s remarks come a day after Canada announced its new ambassador to China.
Business consultant Dominic Barton gained experience working in the region as global managing partner at consulting firm McKinsey, where he spent time based in China.
Chinese foreign ministry spokesman Geng Shuang said on Thursday that Beijing had approved Mr Barton’s appointment.
“We hoped he would play a positive role in getting China-Canada relations back on track,” he said in a news briefing where he reiterated calls for Canada to release Ms Meng.
Mr Barton’s predecessor was fired by Mr Trudeau in January after making controversial comments about the Meng extradition case.