After President Joe Biden ordered a review of intelligence about where the virus emerged, China’s US embassy said that politicizing the origins of COVID-19 would impede further investigations and undermine global efforts to curb the pandemic.

The embassy in Washington said in a statement on its website on Wednesday evening “some political forces have been fixated on political manipulation and (the) blame game.”

As the World Health Organization (WHO) prepares to begin a second phase of studies into the origins of Covid-19, China has been under pressure to give investigators more access amid allegations that SARS-CoV-2 leaked from a laboratory specializing in coronavirus research in the city of Wuhan.

China has repeatedly denied the lab was responsible, saying the US and other countries were trying to distract from their own failures to contain the virus.

Biden said on Wednesday that US intelligence agencies were divided about whether COVID-19 “emerged from human contact with an infected animal or from a laboratory accident”.

Yanzhong Huang, senior fellow for global health with the Council on Foreign Relations in Washington, said China’s reservation was a major factor behind the resurgence of the lab leak theory.

“There’s nothing really new there to prove the hypothesis,” he said. “In the investigation of the origins of the pandemic it is really important to have transparency in order to build trust in the investigation results.”