Recent months have seen the flow of unwelcome undercurrents impeding the good momentum in China-US ties, with Washington labeling unwarranted charges against China over a number of issues. This has raised concerns on both sides. And whether or not the United States Congress approves the renewal of the China-US pact on civil nuclear cooperation will serve as a barometer to gauge the political relations between the two big powers.

On April 21, US President Barack Obama submitted a proposal to the US Congress on continuing the cooperation with China in the peaceful use of nuclear energy. Known as the 123 Agreement under the US Atomic Energy Act of 1954, the pact was signed in 1985 and expires at the end of this year.

The 30-year-old agreement permits transfer of material, equipment (including reactors), components, information and technology for nuclear research and generation of nuclear power. It would provide "a comprehensive framework for peaceful nuclear cooperation with China based on a mutual commitment to nuclear nonproliferation," Obama said.

Yet the concerns and suspicions raised by some Democrats and Republicans in the Congress, evident at a Senate Foreign Relations Committee hearing on May 12, show the extension of the agreement could face a difficult time getting approved. Congressmen are worried that China may not stick to its commitment to nonproliferation and fear that the agreement, if renewed, would allow China to buy reactor coolant technology that could be used to make its submarines quieter and thus more difficult to detect.

Such concerns stem from distrust - the result of the wrong belief that China and the US are rivals, not competitive partners. Since signing of the 123 Agreement, China has entered many international agreements, including the Non-Proliferation Treaty and kept its pledges in practice. Hence, the US Congress should not question China's sincerity in fulfilling its global responsibilities.

Closer cooperation in the peaceful use of nuclear energy will enable the US to tap deeper into China's nuclear power market, the biggest in the world. US-based Westinghouse Electric Company is already building four nuclear reactors in China under a 2005 deal - and six more have been planned - which it values at $25 billion.