In an open letter issued on Friday, the human rights group asked Harper to intervene in the case of Mohamed Fahmy by reaching out to Egypt's president.
"The fact that Mr. Fahmy remains imprisoned, with no clear commitment from Egyptian authorities to release him, points to the necessity of you now becoming involved," the letter said. "Action from you personally is now urgently required."
The call came a day after Foreign Affairs Minister John Baird discussed Fahmy's case with Egypt's foreign minister in Cairo and said Canada hopes for a resolution on the matter "sooner rather than later."
Baird's comments came as a disappointment to Fahmy, who said through his lawyers that he believed Harper "could do more" to secure his release if he were to directly intervene.
Amnesty echoed those sentiments, saying while it appreciated Baird's efforts, Harper needed to ask Egypt to release Fahmy "immediately and unconditionally."
It added that a request from Harper would "carry considerable influence" with Egyptian authorities in general and with Egypt's President Abdel-Fattah el-Sissi in particular.
"After more than one year of unjust imprisonment and mounting concerns about Mr. Fahmy's health and the conditions of his detention, during which time Canada's efforts have not yet led to his release, it is time for the case to be taken up at the highest levels of government," Amnesty said.
Fahmy and two colleagues — Australian Peter Greste and Egyptian Baher Mohamed — were arrested on Dec. 29, 2013, and accused of supporting the banned Islamist Muslim Brotherhood group of ousted Egyptian president Mohammed Morsi. They were also charged with fabricating footage to undermine Egypt's national security.
The trio denied all the allegations against them but after a trial that was internationally criticized, Fahmy and Greste were sentenced to seven years in prison, while Mohamed was sentenced to 10 years.
A retrial has since been ordered in the case after an appeal earlier this month. Meanwhile, Egypt's president has also announced a new decree that gives him the power to deport foreigners convicted or accused of crimes.
Amnesty pointed out that an intervention from Harper, if the prime minister made one, would come at a time when a request for Fahmy's deportation was being considered under the new law.
"The timing for an intervention from you is opportune," Amnesty's letter said. "Applications by Mr. Fahmy and Mr. Greste to be deported from Egypt are pending and offer an avenue for the cases to be resolved under Egyptian law."
Amnesty also noted that the Australian prime minister has raised the case of Greste in meetings with Egypt's president and that U.S. president Barack Obama, as well as British Prime Minister David Cameron have called for the release of all three journalists.
"We urge you to do the same," the letter said.
Baird has noted, however, that it would not be in Fahmy's best interest for Canada to use "threats or tough talk" with Egypt on his case.
Fahmy moved to Canada with his family in 1991, living in Montreal and Vancouver for years before eventually moving abroad for work, which included covering stories for the New York Times and CNN.
He took over as acting bureau chief of Al Jazeera's English-language channel in Cairo in September 2013.
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