The United States President Donald Trump has approved a plan to allow the US navy more freedom to carry out patrols in the South China Sea, in a move that could be seen as a challenge to China’s maritime claims in the disputed waters, reports the South China Morning Post.

The plan, submitted to the White House in April by Defence Secretary Jim Mattis, outlines a full-year schedule of when US navy ships will sail through contested waters in the South China Sea, Breitbart News cited a US official as saying.

Under the plan, the White House will be aware of all planned ‘freedom of navigation operations’ so it will not be ‘a surprise’ when requests come up the chain of command, and they will be approved faster than before, the official said.

The faster approval process means the operations can be conducted on a ‘very routine, very regular’ basis, as part of a programme to keep the waters open, rather than as a ‘one-off event’, the person said.

It is not yet clear if the plan is part of a larger Asia-Pacific strategy or whether it is simply designed to make freedom of navigation operations more routine in the South China Sea.

Under President Obama’s administration, the Pentagon was required to send requests to conduct such operations to the National Security Council, where they would stall, the website report said.

There was a concern ‘of doing anything that would cause anybody to get their feathers ruffled,’ the official was quoted as saying.

Despite tough rhetoric during Trump’s campaign trial, the US did not conduct any freedom of navigation operations in the South China Sea until late May, when the USS Dewey sailed within 12 nautical miles of Mischief Reef in the Spratly Islands.

Mischief Reef is controlled by mainland China, which has built airstrips in the region, but is also claimed by the Philippines, Taiwan and Vietnam.