Speaking to Daily Mail, the reality star revealed that Sarah and Ryan were absent from his birthday because "one's fake" and "one's a clown."
"(It's) very very clear THEY ARE NOT MY FRIENDS, one's fake and one's a clown," Nasser ranted.
Clarifying his statement, Nasser added: "Sarah is fake and pretty boy (Ryan) is a clown."
This is not the first time the fiery personal trainer has clapped back at fellow co-stars.
Earlier this year, when appearing on a radio gig, Ryan said he was "not surprised" by rumours that Nasser was gay.
Nasser responded to Ryan's comments and said: "Look, my sexuality is no-one's business. I will come out with my sexuality in my own time".
Ryan also accused Nasser of setting up staged paparazzi photos - a claim which Nasser furiously denied.
"If Ryan thinks we're making money from photos...I thought we were great mates, I'm very disappointed," Nasser told Daily Mail Australia at the time.
"To bag me on national radio to other bogans saying, 'He's setting up pap shots' - go f**k yourself, mate."
In attendance at Nasser's party were Carly Bowyer and Troy Delmege.