In a new video released Tuesday, a 17-year-old Australian teenager has vowed that the Islamic State group will continue its fight against the West until it succeeds. Abdullah Elmir, who ran away from home and joined ISIS, threatened Prime Minister Tony Abbott and other Western leaders in the latest propaganda video from the Sunni extremist group.

The video identifies Elmir as “Abu Khaled from Australia” and shows him carrying a rifle, surrounded by several other ISIS fighters. He addresses the people of the United States, Britain and “especially the people of Australia,” and refers to the U.S.-led coalition, which was formed to fight the Islamic State group in northern Iraq. In the video, Elmir says that the coalition, regardless of the number of nations supporting it, will not stop ISIS from flying its flag “on top of the Buckingham Palace” and “on top of the White House.”

“To the leaders -- to Obama, to Tony Abbott -- I say this. These weapons that we have, these soldiers, we will not stop fighting. We will not put down our weapons until we reach your lands, until we take the head of every tyrant, and until the black flag is flying high in every single land,” he says, in the video.

The Islamic State group, formerly known as the Islamic State of Iraq and Syria, has killed four hostages since August in brutal beheading videos.

“We will not stop and we will keep on fighting. We will fight you and we will defeat you," Elmir says, in the video.

Elmir reportedly disappeared from his home in Sydney in June along with another Australian teenager. Elmir's family has said that he has been “brainwashed” and are trying to find out how he reached Turkey from Sydney, The Australian, a local newspaper, reported.

Abbott said, in a statement, that the video "again highlights the threat posed by ISIL [Islamic State],” ABC News reported. "ISIL is a threat that reaches out to Australia and our allies and partners."

Australia is participating in the U.S.-led international coalition against ISIS and its fighter jets are carrying out airstrikes to fight the group in Iraq.