The plea means Hiva Mohammad Alizadeh, 34, will not face trial in February as previously expected.
Alizadeh, who once studied electrical engineering technology in Winnipeg, was arrested in August 2010 as part of an alleged extremist conspiracy.
Police seized terrorist literature, videos and manuals along with dozens of electronic circuit boards — gadgets the Crown says were designed to detonate homemade bombs remotely.
As part of a deal with the Crown, Alizadeh will be sentenced to 24 years in prison.
After accounting for time served — credited as six years — Alizadeh faces a maximum of 18 more years behind bars, and he has agreed not to apply for parole for at least nine years.
Two other terrorism-related charges against Alizadeh have been dropped.
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