Chinese media criticised the US on Thursday for "ceaseless provocations" in the South China Sea, with Washington expected to soon send warships close to artificial islands Beijing has built in disputed waters.

An editorial in the Global Times, which is close to China's ruling Communist party, condemned US "coercion", adding: "China mustn't tolerate rampant US violations of China's adjacent waters and the skies over those expanding islands."

It said China's military should "be ready to launch countermeasures according to Washington's level of provocation".

Tensions have mounted since China transformed reefs in the area – also claimed by several neighbouring countries – into small islands capable of supporting military facilities, a move the US says threatens freedom of navigation.

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