Australia's prime minister says one of two men charged with planning to launch an imminent terrorist attack in Australia appeared on a video threatening to stab the kidneys and necks of their victims.

Omar Al-Kutobi and Mohammad Kiad were charged this week with planning a terrorist act after police raided their Sydney home and seized the video, a homemade flag associated with the Islamic State group, a machete and a hunting knife.

Prime Minister Tony Abbott said Thursday that the video shows one of the men saying: "We will carry out the first operation for the soldiers of the caliphate in Australia. ... I swear to almighty Allah, blond people, there is no room for blame between you and us. We only owe you stabbing the kidneys and striking necks."