The Bush administration imposed sanctions Saturday on a Chinese arms producer for selling missile technology to Pakistan, a State Department official said.

China is not supposed to export missile technology to nations developing nuclear missiles, according to an agreement with the United States. State Department officials long have accused Beijing of ignoring the accord.

The Chinese company is China Metallurgical Equipment Corp., which has worked with the Chinese government, said the official, speaking on condition of anonymity. Also punished was the National Development Complex of Pakistan.

"The sanctions were imposed on these entities for their involvement in the transfer ... of missile technology that contributed to Pakistan's missile program," the official said.

The penalties will keep U.S. companies from issuing licenses to launch satellites on Chinese rockets and, in most cases, will make it illegal to provide technology to China's satellite industry.

The technology the Chinese arms dealer is accused of exporting is considered category 2 technology, which includes flight-control systems for missiles and rocket components.

The announcement comes in the month before President Bush's planned trip to China. State Department officials are hoping his visit will help ease tensions after the crash of a U.S. spy plane and a Chinese fighter jet in April.

U.S. suspicions of arms deals between China and Pakistan have been building for months.

Talks between U.S. and Chinese weapons experts last week over whether China is helping other countries develop missile technology ended with the American side wanting more answers, U.S. officials said.

The officials said they worried that Chinese firms provided missile technology to Pakistan and helped Iraq rebuild air defenses. Vann Van Diepen, an acting deputy assistant secretary of state who specializes in nonproliferation issues, led the U.S. negotiators.

In July, Secretary of State Colin Powell met with Chinese leaders and said that the U.S. felt China was not following the arms agreement.

A Chinese Foreign Ministry spokesman, Sun Yuxi, responded that China was making an earnest effort to comply with its obligations.

Sun contended that the United States has failed to comply with its commitments – an apparent reference to the absence of cooperation on commercial satellite launches.