A US court panel has ruled that an Australian couple can proceed with a lawsuit which alleges that their idea for a shape-shifting creature was used without permission in the film Terminator 2.

Filia and Constantinos Kourtis claim that they came up with the character in 1987 and hired a writer, William Green, to write a screenplay, and they allege that the screenplay was shared with James Cameron, who directed and co-wrote Terminator 2.

Mr Green, who claimed he owned copyright for the screenplay, filed an infringement lawsuit against Cameron and others after the film was released, but the suit was dismissed.

The Kourtises later challenged Green's ownership of the script in an Australian court and prevailed in 1998. The couple then filed their own lawsuit against Cameron, alleging that he used their concept without providing payment or attribution, but it was dismissed.

They appealed and a panel agreed on Monday that they should have their day in court.