The Pentagon said on Saturday it regretted China's suspension of military exchanges over a controversial $6.4-billion-US arms package for Taiwan.
Beijing announced it was cutting military and security contact with the United States after Washington announced on Friday a deal to sell Patriot missiles, Black Hawk helicopters and communications equipment for Taiwan's F-16 fleet of fighter jets among other weaponry.
"We regret that the Chinese side has curtailed military-to-military and other exchanges," Pentagon spokesman Geoff Morrell told AFP.
"We also regret Chinese action against US firms transferring defensive articles to Taiwan."
State Department spokeswoman Laura Tischler said the deal, which stopped short of agreeing to Taiwan's long-standing request to transfer more of the F-16 jets themselves, "contributes to maintaining security and stability across the Taiwan Strait."
The last US arms package for Taiwan, announced under Obama's predecessor George W. Bush in October 2008, also led China to cut off military relations with the United States temporarily.
But this time the sanctions were more biting, and analysts said they reflected China's increased clout at a time when its economy looks set to overhaul Japan's and its military budget is surging year by year.
Chinese defense ministry spokesman Huang Xueping said the reprisals reflected the "severe harm" posed by the deal with Taiwan, which Beijing says is a part of its territory that must return to the mainland fold.
The trade of barbs amounted to the worst Sino-US crisis of US President Barack Obama's tenure so far.
US officials said the White House was committed to Taiwan's defense, and denied it was picking a fight with China.
China refuses to rule out the use of force to reacquire Taiwan, and has hundreds of missiles deployed against the self-governing island of 23 million people, which split from the mainland in 1949.