China is threatening to impose sanctions on US arms firms and cut cooperation with Washington.
This in a row over plans for a multi-billion-euro plan to sell US weapons to Taiwan.
This is the latest in a deepening rift between Beijing and Washington, with tension already building over trade, currency, Tibet and the internet.
Philip Crowley from the US State Department said:
“No, we did not consult with China before taking this action. We did notify the PRC before this action, just as we notified Taiwan before the notification was sent forward.”
The Taiwanese President, Ma Ying-Jeou, said: “The weapons sale decision will help with our defences and be an effective deterrent and also allow us to have more confidence and sense of security in developing cross-Strait relations.”
China is calling on the US to immediately reverse what it calls a “mistaken” decision to supply arms to Taiwan, a self-ruled island that Beijing views as an illegitimate breakaway province.
The Obama administration told Congress on Friday about plans to supply Black Hawk helicopters, missiles and two mine-hunting ships.