South China Sea installations 'primarily' civilian: Li

Analysis shows significant weaponry on artificial islands that China has built in the South China Sea, including anti-aircraft guns

China is not militarising the disputed South China Sea, the country's premier insisted in Australia on Friday, claiming defence equipment Beijing has installed on artificial islands is "primarily" for civilian use.

The sea is a source of growing regional tension, with Beijing insisting it has sovereignty over virtually all the resource-rich waters, which are also claimed in part by a handful of other countries, and deemed international waters by most of the world.

"Even if there is a certain amount of defence equipment or facilities, it is for maintaining the freedom of navigation," Premier Li Keqiang told reporters in Canberra during a press conference with Australia Prime Minister Malcolm Turnbull.

"Because without such freedom, or without stability in the South China Sea, the Chinese side would be among the first to bear the brunt of it."

China "never has any intention to engage in militarisation in the South China Sea", he said, adding installations -- which include airstrips and missile batteries -- are "primarily for civilian purposes".

Li said aircraft and ships that transit through the South China Sea were from trading partners with Beijing, "so one can easily imagine how many Chinese interests are at stake here".

Australia has followed key ally the United States in carrying out several so-called "Freedom of Navigation" over-flights and sail-bys in the region, which China previously described as "provocations".

Foreign Minister Julie Bishop has also said the building of artificial islands and possible militarisation by China create regional mistrust.

Turnbull reiterated his call for all parties to resolve their differences peacefully under international law.

"We encourage all parties to refrain from taking any actions which would add to tensions, including actions of militarisation of disputed features," he added.