The United States on Wednesday announced sanctions and restrictions on two dozen Chinese companies and associated officials for taking part in building artificial islands in disputed waters in the South China Sea.

The 24 state-owned firms include subsidiaries of construction giant China Communications Construction Co., telecommunications firms and a unit of the China Shipbuilding Group.

The move was the latest step in Washington's efforts to pressure Beijing over its military buildup in areas of the South China Sea where sovereignty is contested by several countries.

The US Commerce Department said the companies "enabled China to construct and militarize disputed outposts in the South China Sea."

"Since 2013, the PRC (People's Republic of China) has used its state-owned enterprises to dredge and reclaim more than 3,000 acres on disputed features in the South China Sea, destabilizing the region, trampling on the sovereign rights of its neighbors, and causing untold environmental devastation," Secretary of State Mike Pompeo said in a statement.

The 24 companies were placed on the Commerce Department's "Entity List" which allows it to block exports of US goods and materials to them.

In addition, Pompeo said individuals associated with the South China Sea operations will be unable to obtain visas to visit the United States.

The names of the individuals were not made available.