The actor - who has previously been romantically linked to Kirsten Dunst and Mischa Barton - amazed fellow guests at Channing Tatum`s 30th birthday party on 24.04.10 by spending the majority of the evening with the Australian beauty.
The pair arrived together for the private dinner at Macao Trading Co. in New York, where they retreated to a back corner table for most of the night.
A source told the New York Post newspaper: "They turned up after midnight... they definitely looked like a couple."
Josh and Abbie`s appearance together comes less than a week after they were seen enjoying an intimate dinner at a New York restaurant.
Other guests at the party, which was hosted by artist and Dactyl Foundation founder Neil Grayson, included Channing`s actress wife, Jenna Dewan, and his `Son of No One` co-stars James Ransone and Ray Liotta.
Abbie has been single since February, when she and long-term partner Ryan Phillippe - who she had been dating for just under three years - ended their relationship.