The Pentagon notified the U.S. Congress Tuesday about a possible sale to Taiwan of an upgrade to its Patriot missile defense systems valued at nearly one billion dollars.
Even before the announcement, the proposed sale was attacked by China as sending a "wrong signal" to Taiwan and its independence-minded President Chen Shui-bian.
The Defense Security and Cooperation Agency said the upgrades would involve ground support equipment of three existing Patriot fire units.
"The proposed sale will help improve the security of the recipient and assist in maintaining political stability, military balance and economic progress in the region," the DSCA said.
The Pentagon estimates that China has nearly 1,000 short range ballistic missiles deployed within striking distance of Taiwan, and is developing other capabilities aimed at preventing outside military intervention in the early days of a cross-straits conflict.
In meetings last week US Defense Secretary Robert Gates, Chinese leaders raised their concerns that Chen intends to move Taiwain toward "de jure" independence through a referendum next year on UN membership.
Gates assured President Hu Jintao that the United States was "categorically opposed" to a change of status for Taiwan, but also raised US concerns about China's military buildup.
China's foreign ministry spokesman Liu Jianchao said in a statement that the latest Patriot upgrade violated a US commitment to reduce weapons transfers to Taiwan, which Beijing regards as a renegade province.
"We urge the US side to implement with real actions its solemn commitments on the Taiwan issue... and stop sending wrong signals to Taiwan," he said.
He said the Pentagon announcement constituted "rude interference in China's internal affairs."
"The Chinese side strongly protests against this and has raised solemn representations with the United States," Liu said.
"The Chinese side reserves the right to adopt further measures," he said without elaborating.
China had a similar reaction in September after the Pentagon announced the possible sales to Taiwan of a dozen P-3C Orion anti-submarine patrol aircraft and SM-2 anti-aircraft missiles worth more than 2.2 billion dollars.
The Patriot fire units would be upgraded with new radios, radars, target identification and remote launch systems, and electric power plants, the DSCA said.
"The total value, if all options are exercised, could be as high as 939 million dollars," it said in a statement.
The prime contractor will be Raytheon Corporation, of Andover, Massachusetts.
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