China threatened US firms who sells weapons to Taiwan with sanctions, as Beijing ratcheted up the pressure in a ballooning crisis that will widen already deep rifts in their relationship.
The Foreign Ministry, Defence Ministry and China's Taiwan Affairs Office all piled in with their own dire warnings, including that arms sales would affect Sino-US co-operation on major international and regional issues.
"The United States must be responsible for the serious repercussions if it does not immediately reverse the mistaken decision to sell Taiwan weapons," Chinese Vice Foreign Minister He Yafei told the US ambassador to China, Jon Huntsman.
He said Taiwan was the "most important and most sensitive core issue in Sino-US relations," in comments carried on the Foreign Ministry's website.
The Obama administration told the US Congress on Friday of the proposed sales to Taiwan, a potential $6.4 billion (Dh23.5bn) package including Black Hawk helicopters.
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