Foreign Minister Julie Bishop says Australians should be shocked by a video, showing children as young as six chanting anti-Western rhetoric and waving Islamic extremist flags.

A Muslim youth group at Lakemba in Sydney's southwest has been accused of indoctrinating young children, after the Seven Network's airing of YouTube footage of a performance.

Four boys, aged six to 13, wave flags, including that used by Islamic State, and chant "You're never too young to be a Soldier for Khilafa".

They call for US President Barack Obama to go to hell, and say they want the head of Syrian President Bashar al-Assad.

Ms Bishop says children should be playing in their playgrounds with friends, not being enlisted by irresponsible adults to an ideology that preaches hatred against the country in which they live.