Vin Diesel has hailed 'Fast & Furious 7' as ''incredible'' in a Facebook post previewing the new film.

The action hero - who recently starred in 'Guardians of the Galaxy' - has teased the trailer to the new movie, saying watching the promo was ''emotional and bittersweet'', referring specifically to an image of himself with late co-star Paul Walker.

His post reads: ''Universal came to visit, to show the trailer for FF7. Speechless... yeah, it was that INCREDIBLE! (sic)''

The 47-year-old actor added that he wished Walker was around to see the new film for himself.

He said: ''I must also say, that it was emotional and bittersweet.

''We all went above and beyond to make Pablo [Walker's nickname] proud, but man, I wish he could see what we have created and just how far we have come.''

The new film, which is set for release on April 3, 2015, boasts a star-studded cast that includes Dwayne Johnson, Michelle Rodriguez and Tyrese Gibson, as well as Jason Statham and Kurt Russell.

What's more, Vin Diesel revealed in an interview with French radio station Skyrock FM that Iggy Azalea is to make a cameo appearance in 'Fast & Furious 7'.