(Bloomberg) -- China defended its measures to curb the virus outbreak and expressed displeasure with the U.S. over what it calls a “groundless accusation” of Chinese pandemic policies, even as cases in Shanghai continued to spread despite an extensive lockdown.

Shanghai reported a record 24,943 new Covid cases on Saturday, according to the municipal government. That’s more than five times the number seen on March 28, when 4,477 infections were reported as the city first imposed a lockdown. Total new infections in China on Saturday were at 26,355.

The U.S. State Department asked Americans to reconsider travel to China and avoid visiting virus hotspots including Shanghai due to what it calls an “arbitrary enforcement” of virus restrictions. It also allowed non-emergency employees and their family members from the U.S. consulate in Shanghai to leave, and notified Chinese officials of the voluntary departure decision while raising concerns regarding China’s Covid response.

“The U.S. announcement of authorizing the voluntary departure of U.S. personnel and their family members at the U.S. Consulate General in Shanghai is the U.S.’ own decision,” China’s foreign ministry spokesperson Zhao Lijian said in a statement. “However, it should be pointed out that China’s anti-epidemic policies are science-based and effective, and we are fully confident that Shanghai and other places in China will prevail over the new wave of the epidemic.”

China is struggling to stop the hyper-infectious omicron variant with lockdowns in several cities and repeated mass testing as it clings to a zero-tolerance approach. Known as Covid Zero, the strategy has become less effective in preventing domestic flareups due to the growing contagiousness of new variants and more disruptive to economic activities and people’s lives. 

“We are strongly dissatisfied with and firmly opposed to the U.S. side’s groundless accusation against China’s epidemic response policies, and have lodged solemn representations with the U.S. side,” Zhao said. 

China’s adherence to Covid Zero has left the country increasingly isolated in a world that have largely moved to reopening borders and living with the virus.

Shanghai’s infection count keeps climbing despite the city’s move to lock down its 25 million people in two phases starting on March 28. While there has been some adjustments to allow people some movement, there is no clarity when the restrictions will be lifted despite an increasing desperation among the population to get access to food and medical care. 

Shanghai, Guangzhou Plan More Mass Tests as Covid Cases Rise

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