The remarks, from Li Changjiang, head of China's General Administration for Quality Supervision, Inspection and Quarantine, are aimed at US manufacturers and in particular Mattel, following its recent well-documented product recall.
Changjiang also promised, however, to punish China’s own manufacturers who flout standards.
"I myself looked at some of the samples of these problematic toys, and I found that there is a serious problem with the design. The design is seriously defective," said Changjiang.
"In my view, no matter where those toys were sold there would be a recall, because it is highly likely they are dangerous for children.
"While we recognise that Chinese producers should be blamed for those problematic toys, what kind of responsibility should the U.S. designers and the US importers take in this respect?".
China is facing growing global pressure to clean up its manufacturing sector and ensure the quality of its exports after a series of scandals involving products ranging from poisonous pet food ingredients to sub-standard toys and tainted toothpaste.
Changjiang also blamed differing national standards, misleading statistics and lack of communication for some of the product safety scares that have alarmed foreign consumers.
"For some products, the two countries enforce different standards," Li said of China and the United States, also citing "inaccurate statistics".
But he said the latest Chinese campaign to improve product safety would focus on creating a chain of supervision across the entire production process for both industrial products and food.
The country's certification body also plans to strengthen controls of export permits for toys.