Robert Pattinson's strained relationship with his sometime love Nikki Reed is creating awkward moments for the New Moon co-stars off set too. Rob seemed irked when Nikki crashed his night out with castmates Kellan Lutz, Ashley Greene and a few other friends at Boneta Restaurant in Vancouver, British Columbia, on April 13. "When Nikki arrived, Robert didn't get up to say hi," says an eyewitness. Rob ignored Nikki most of the night as he chatted up her pal Sage "Cecil" Dills and the rest of the cast. Then after finishing his glass of wine 10 minutes before midnight, Rob made his goodbye rounds, giving big hugs to everyone -- except Nikki. "He gave her a weak high-five as she tried to put on a big smile," continues the onlooker, "but Rob just wasn't having it."

For more on Rob and Nikki's relationship and the five reasons why Rob is the sexiest man on Earth, pick up the latest issue of Life & Style, on newsstands now!

Photo Credit: Abaca