The switch to North America makes him the first Tunisian player to join a Major League Soccer club in their 25 years of existence.
Khmiri's signing comes as reinforcement for the BC Place outfit ahead of their league opener Minnesota United on March 3.
And manager Marc Dos Santos is raving about the abilities of the centre-back that will help shore up their defence in the upcoming 2019 season.
“Jasser is a player who caught our eye thanks to his strong performances with the Tunisian U-21 national team,” Dos Santos told club website.
“He’s 6-foot-4, he has very good speed, and he’s comfortable with the ball, which are all qualities we are looking for in a centre back.
"At 21 years old, we believe Jasser has a tremendous upside and that he can become an important player for this club.”