China continued on the offensive on Monday as it demands answers from the US over unsubstantiated claims it is funding biological weapons in Ukraine.
It comes amid mounting tensions that have led to the US warning China not to help Russia with its invasion of Ukraine.
Beijing has followed the lead of Russia and peddled claims labs creating biological weapons have been discovered by Russian forces following their invasion of Ukraine.
Russia has claimed US-sponsored labs in Kyiv, Kharkiv and Odessa were unearthed that were creating dangerous pathogens custom-designed to target Russians and other Slavs.
The US has categorically rejected the claims as misinformation, and states its involvement in bio-labs in Ukraine is on the basis of ensuring "Ukraine can detect and report outbreaks caused by dangerous pathogens before they pose security or stability threats".
China demands answers from US
Yet on Monday evening, China's foreign ministry spokesperson Zhao Lijian said the US's explanation was unsatisfactory and issued six questions Beijing was seeking answers to from Washington.
Pressed on US ambassador to the UN Linda Thomas-Greenfield's comments who dismissed Russia and China's claims, Mr Zhao asked:
If the concerns are “disinformation”, why doesn’t the US release detailed materials to prove its innocence?
What did the US spend the $200 million [invested in the labs] on?
What kind of research has the US conducted on which pathogens?
What is it trying to hide when the US Embassy in Ukraine deleted all relevant documents on its website?
Why does the US insist on being the only country in the world to oppose the establishment of a multilateral verification mechanism, though it claims to abide by the Biological Weapons Convention (BWC)?
If the US wants to prove its innocence, why doesn’t it open up these bio-labs for independent investigations by international experts?
Mr Zhao was pressed by the BBC on question four, refuting his claim and stating such material was still live online.
Amid a tense exchange, he hit back stating the US's response to the accusations have been "self-contradictory and perplexing".
US warns China over Russia help: 'We will not allow it'
It comes as the US warned China not to help Russia's invasion of Ukraine. US officials claim Russia has asked Beijing for military and economic aid.
"We have communicated very clearly to Beijing that we won't stand by," State Department spokesman Ned Price told reporters on Monday.
"We will not allow any country to compensate Russia for its losses."
Mr Zhao rejected such a suggestion, saying the US has been "been maliciously spreading disinformation targeting China".
"China’s position on the Ukraine issue is consistent and clear. We have been playing a constructive part in promoting peace talks. The top priority at the moment is for all parties to exercise restraint, cool the situation down instead of adding fuel to the fire," he said.
However China has faced mounting criticism for its refusal to label Russia's advancements an invasion, while suggesting US-led NATO's development eastwards provoked the war.
While several countries have ramped up sanctions against Russia, Australian Prime Minister Scott Morrison lashed out at Beijing who he said had "thrown a lifeline to Russia" by approving imports barred by other countries.
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