WASHINGTON, Aug. 15 — Chinese government authorities are prepared to require that every shipment of food being exported to the United States and other countries be inspected for quality by the government, starting Sept. 1, a senior Chinese trade official said on Wednesday.

Zhao Baoqing, who is based at the Chinese Embassy in Washington, said that all types of food would be inspected with at least one box in each shipment checked and that each package or shipment would be affixed with a government seal.

The pledge came at a hastily called briefing for reporters in Washington intended to address the growing furor among officials here and American consumers nationwide over the surging numbers of Chinese food, drugs, toys and other products that are being recalled or identified as potentially hazardous. “China is very concerned about food safety,” Mr. Zhao said. “What we want is to allow the consumers to rest assured when they use products imported from China.” Mr. Zhao said negotiations were also taking place with officials from the Consumer Product Safety Commission in Washington to find ways to ensure that toys and other products being sent to the United States did not contain lead or other hazards.

In recent weeks, the Chinese government has increased its inspections of toys subject to export.

But he said the government would oppose any mandate that importers hire independent safety laboratories to test all of the Chinese toys destined for the United States. It would also oppose deploying United States government toy inspectors to China.

“They can come to train us and tell us the rules,” he said. “But inspection is a country’s sole authority.”

The unusual briefing, in a windowless auditorium at the Chinese Embassy before a giant tapestry of the Great Wall of China, gave the Chinese government an opportunity to admit that as a fast-growing and still-developing nation, it needs to improve the quality of goods it exports.

“We are resolved to ensure greater safety of Chinese products,” he said.

But Mr. Zhao, a former senior official in China’s federal food and product safety agency, was also defiant, saying that he believed the danger presented by Chinese products had been exaggerated. And the United States, he said, has sent flawed products to China, including generators and cotton harvesting machinery.

Previous vows to step up inspections in China have been met with skepticism, because many exporters of food have a tradition of mislabeling goods and shipping them illegally. The country’s food safety enforcement program has historically been weak, and even prone to corruption and bribery.

The recent string of cases involving products from China — including recalls or warnings about hazardous food, toothpaste, fish, tires and toys — has inspired the Chinese government to step up its own safety efforts, he said, both through increasing inspections of goods headed for export and through investigations of companies suspected of violating the law.

He said the government had already apprehended people involved with the mislabeling of puffer fish as monk fish, as well as companies involved in adding hazardous ingredients to pet food. And it is actively investigating a Chinese vendor who apparently sold lead-contaminated paint to a supplier to Mattel, which led to its recent recall of lead-coated toys.

The enhanced food inspections, he said, would not mean that every box of food would be inspected by a government official. Instead, every shipment will be checked at some point along the production line, and a higher percent of the food in individual shipments will be physically checked, he said.

Officials in Washington have made clear that they think the Chinese government — and exporters based there — have not done enough to ensure that exported good are safe.

“There is no question that too many Chinese manufacturers and food producers put the bottom line ahead of safety,” Senator Charles E. Schumer, Democrat of New York, said in a statement on Wednesday.

Mr. Schumer is among those who intend to call for the placement of United States safety regulators inside toy factories in China.

Mr. Zhao said that the Chinese government planned to announce by mid-September a new agreement with American regulators and toy importers to address concerns over toy hazards.

American officials have hinted this will include a requirement for more inspections, paid for by toy importers. Mr. Zhao said the Chinese government had no objection to these third-party inspections, but did not want them to be a precondition of toy exports from China.