Email i just received from Aliexpress.
Australia GST Tax Notice
Hello,
From 1 July 2018, Australian goods and services tax (GST) 10% will apply to each order valued at A$1,000 or less, and AliExpress is required by law to collect such GST and remit to Australian Taxation Office.
For more information, please visit :
https://www.ato.gov.au/Business/International-tax-for-busine….
Sincerely,
AliExpress.com
Received the same notice overnight. Reality is though that AliExpress is not "required by law to collect such GST" as the Australian Government has no ability to impose such a law on a foreign entity. They have even said this.