China has repeated its warning to the United States not to sell arms to Taiwan, and to stop interfering in China's internal affairs.
Strongly opposing official exchanges and military ties between the US and Taiwan, the spokesman for China's policymaking Taiwan Affairs Office An Fengshan also said yesterday that any attempts at Taiwan independence will meet a dead end.
Mr An's comments came after recent escalations in US-China tensions that threaten to spill over beyond the ongoing trade war and into other domains.
Reports last week said the US is pursuing a US$2 billion (S$2.72 billion) arms sale to Taiwan consisting of 108 Abrams tanks and a range of portable anti-tank missiles, angering Beijing.
China's Foreign Ministry had slammed the proposed arms sale, which would be the fourth such deal for Taiwan under President Donald Trump if it is approved by Congress.
The proposed deal comes on the back of a US$330 million sale of F-16 and other military aircraft parts last year, and an F-16 pilot training, maintenance and logistics support programme worth some US$500 million that was approved in April.
Yesterday, Mr An reiterated the Foreign Ministry's call for the US to sever military ties with Taiwan and to avoid upsetting stability in the Taiwan Strait.
"The situation in the Taiwan Strait is, at present, complicated and serious, and the US should handle Taiwan-related issues with caution and not send the wrong signals to 'Taiwan independence' separatist forces," he said.
The Pentagon has in recent months increased the frequency of naval patrols through the Taiwan Strait, in what officials call freedom of navigation exercises.
Earlier this month, the US released its first Indo-Pacific Strategy Report that included Taiwan on a list of those it called "reliable, capable and natural partners of the United States".
Washington timed the release of the report with Acting US Defence Secretary Patrick Shanahan's speech at the Shangri-La Dialogue in Singapore, where he said the US would no longer "tiptoe" around China's behaviour in Asia.
The US Pacific Marine Corps has since released photos of a Taiwanese general at an annual gathering of military leaders in Hawaii last week. The White House this month also posted on Instagram a photo of Mr Trump with US Air Force Academy graduates, with the Taiwan flag visible on the side.
China considers self-governed Taiwan a renegade province with no right to state-to-state ties, and territory to be "reunified" by force if necessary.
Mr An did not directly answer whether China viewed these latest developments as having breached its bottom line regarding the mainland's "one China" principle, but said Taiwan is an inalienable part of China.
China takes the position that there is one China, with each side having different interpretations of what "one China" means.
Mr An said China will not tolerate any attempt to divide the country, and that Beijing "reserves the option to take all necessary measures targeting interference by external forces and the separatist activities of a very small number of 'Taiwan independence' separatist forces".
"There is only one China in the world; Taiwan is an inalienable part of China, and Taiwan has never been a country," he said. "This fact has never changed and cannot be changed."