A bipartisan group of senators sent a letter to the Chinese ambassador to the United States on Thursday that criticizes Beijing's establishment of an air defense identification zone and recognizes the Senkaku Islands as being under Japanese control.
The four members of the Senate Foreign Relations Committee, including Chairman Robert Menendez, said in the letter to Cui Tiankai that they view the unilateral ADIZ declaration as "an ill-conceived attempt to alter the status quo."
"China's declaration of an ADIZ over areas of the East China Sea does not alter the U.S. acknowledgement of Japan's administrative control over the Senkaku Islands," the letter said.
The senators include Bob Corker, the ranking Republican on the committee.
The senators took the action because of the U.S. government's strong reaction to the ADIZ, which overlaps similar zones previously set up by Japan, South Korea and Taiwan.
China is also demanding that all aircraft entering the zone submit flight plans and has cited the possibility of military action.
Washington has said the bilateral security treaty with Japan, under which the United States is required to defend Japan, covers the Senkakus.
"This declaration reinforces the perception that China prefers coercion over rule of law mechanisms to address territorial, sovereignty or jurisdictional issues in the Asia-Pacific," the letter said.
Given that China is involved in territorial disputes in the South China Sea with countries such as the Philippines and Vietnam, the senators urged Beijing not to implement the ADIZ and to "refrain from taking similar provocative actions elsewhere in the region."
The Senate unanimously adopted a resolution in July that condemned "the use of coercion, threats or force" in the South China Sea and the East China Sea to assert disputed maritime or territorial claims or alter the status quo.