World Premiere Of Fast & Furious 6Vin Diesel has been vocal about his grief over the sudden passing of co-star Paul Walker, and continued to pay tribute to his late friend during a recent screening of their last film together, "Furious 7."

At the event, which took place in Los Angeles last week, Diesel told attendees that the film was a "labor of love" that honored Walker. "Furious 7" was in the middle of filming when Walker, 39, died in a car crash in November 2013, delaying production.

"It was in some ways the hardest movie I ever had to do because the relationships that you see on film are so real," Diesel said at the screening. "When the tragedy happened, I lost my best friend. I lost my brother."

Diesel added that cast and crew "made this movie from our hearts," and said that the film was "our gift" to the fans, as well as Walker.

"Furious 7" will be dedicated to Walker's memory. It's due in theaters on April 3.

[via: People]

Photo credit: Getty Images for Universal Pictures