The move is likely to anger Beijing as President Donald Trump seeks its continued co-operation on North Korea.
The US officials, speaking on the condition of anonymity, said the USS Higgins guided-missile destroyer and the USS Antietam, a guided-missile cruiser, came within 12 nautical miles (22km) of the Paracel Islands, among a string of islets, reefs and shoals over which China has territorial disputes with its neighbors.
Both ships appear to have recently departed deployment in the Arabian Sea. They appear to have undertaken what the United States calls a “Freedom of Navigation Exercise” en route to their home ports.
China maintains the islands are its sovereign territory. Several other nearby nations also make that claim. But many of the islands are not even recognized as islands under international law. Any artificial modification of a reef or shoal does not change its status.
China has embarked on an enormous engineering project in recent years, turning many contested outcrops into enormous fortresses, complete with airfields and harbors. Beijing has arbitrarily claimed ownership of more than 80 per cent of the South China Sea. Its claim that this is part of its historical heritage was recently rejected by an international court of arbitration.
The US military vessels carried out maneuvring operations near Tree, Lincoln, Triton and Woody islands in the Paracels, one of the officials said.