Samsung is suing Apple to stop sales of the iPhone 4S in Australia, just days after the device went on sale around the world.

Both companies are now shelling out millions in legal fees to fight more than 20 patent infringement cases in 10 countries. Samsung recently vowed to shift its strategy from "passive" to being "more aggressive" in targeting Apple for "free riding" on its patents.

Apple's iPhone 4S. Credit:Adam Turner

Samsung filed a suit seeking a ban on sales of the iPhone 4S in the Federal Court's New South Wales Registry today, and separately lodged an appeal against last week's decision by the court to temporarily ban sales of its Galaxy Tab 10.1 in Australia.

Suits against the iPhone 4S had already been launched in Italy and France but today Samsung filed preliminary injunction motions in Tokyo and Australia. A similar case in the Netherlands was dismissed on Friday.