WASHINGTON/HONGKONG: China has denied a request for a US carrier strike group led by the USS John C. Stennis to visit to Hong Kong, the US Defense Department said on Friday, amid heightened tensions over China’s territorial claims in the South China Sea.

A Pentagon spokesman, Commander Bill Urban, said a US warship, the USS Blue Ridge, was currently in Hong Kong on a port visit and the United States expected that to continue.

The Chinese government and its embassy in Washington did not immediately respond to requests for comment.

Urban said the request for the Hong Kong visit by the carrier and its accompanying vessels, which have been patrolling the South China Sea, was recently denied, despite a “long track record of successful port visits to Hong Kong.”

The Blue Ridge, the command ship of the US Seventh Fleet, arrived in Hong Kong waters at 11:20 a.m. local time (0320 GMT) on Friday, according to the on-line log of the Hong Kong government’s Marine Department.

The nuclear-powered Stennis has been conducting patrols in the South China Sea, which China claims most of and where Beijing has sparked US and regional concerns by building artificial islands to bolster its claims.

US Defense Secretary Ash Carter visited the Stennis while it transited the South China Sea on April 15 to underscore US concerns about the need to maintain freedom of navigation in the South China Sea in the face of Chinese moves.

A wide range of US military vessels and aircraft have long routinely stopped in Hong Kong, a reflection of the “one country, two systems” formula under which Britain handed the global financial hub back to China in 1997.

The visits occasionally have been suspended in periods of heightened tensions, such as after a mid-air collision between a US EP-3 surveillance plane and a Chinese plane off China’s Hainan island in 2001.

The USS Kitty Hawk aircraft carrier also was denied permission to enter Hong Kong over Thanksgiving in 2007 but was cleared to visit five months later.