File photo of An Fengshan, spokesperson with the State Council Taiwan Affairs Office. [Photo: gwytb.gov.cn]

A spokesman on Wednesday reiterated China's opposition to foreign interference in Taiwan affairs, saying the fate of the island should be decided by the 1.3 billion Chinese people living across the Taiwan Straits.

An Fengshan, spokesman for the Taiwan Affairs Office of the State Council, made the remarks when asked to comment on US President Donald Trump's Taiwan policy.

Describing Taiwan's unification with the mainland as an unstoppable historic trend, An said "anyone trying to fight the trend by borrowing influence from foreign powers will ultimately harm the immediate interests of the Taiwan people."  

"The status of Taiwan is an internal affair for China and we firmly oppose to any foreign interference," said An.

He added that China will strive for peaceful unification with utmost sincerity, and will stand firm in safeguarding national sovereignty and territorial integrity.

The spokesman also weighed in on a US State Department spokesperson's criticism on El Salvador's decision to establish diplomatic relations with China, saying the United States is adopting double standards and has violated its one-China policy.