China reiterated opposition over political manipulation on the origins-tracing of the coronavirus on Wednesday, urging the United States to reflect on itself rather than shift blame and indulge in conspiracy theories.

Foreign Ministry spokesman Guo Jiakun made the remarks in response to recent US media reports claiming that the US Agency for International Development used US taxpayers' money to fund gain-of-functions studies of the virus at China's Wuhan Institute of Virology, which allegedly has caused COVID-19 pandemic and led to the deaths of millions worldwide.

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China has made it clear many times that the Wuhan Institute of Virology has never engaged in gain-of-function studies of coronavirus and never designed, made or leaked COVID-19, Guo emphasized.

It is extremely unlikely that the pandemic was caused by a lab leak, which is the authoritative conclusion reached by the experts of the WHO-China joint mission, he said.

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The conclusion is based on science following their field trips to the labs in Wuhan and in-depth communication with researchers, Guo said, adding that the conclusion has been widely acknowledged by the international community, including the science community.

Origins-tracing of COVID-19 is a matter of science and any judgment on it should be made in a science-based spirit by scientists, he added.