The United States and China on Friday took their growing clash over the coronavirus pandemic to social media, with Beijing telling Secretary of State Mike Pompeo he was "lying through (his) teeth."

In an interview on Fox News, Pompeo said Beijing "wasted valuable days" after identifying the novel coronavirus by letting "hundreds of thousands" leave the epicenter of Wuhan to places including Italy, which has surpassed China as the country with the highest death toll.

"The Chinese Communist Party didn't get it right and put countless lives at risk as a result of that," Pompeo said.

Chinese foreign ministry spokeswoman Hua Chunying voiced anger on Twitter, writing in English: "Stop lying through your teeth!"

"As WHO experts said, China's efforts averted hundreds of thousands of infection cases," she tweeted.

She said that China first told the United States of the novel coronavirus outbreak on January 3, with the State Department alerting Americans in Wuhan on January 15.

"And now blame China for delay? Seriously?" she wrote.

State Department spokeswoman Morgan Ortagus replied: "By Jan. 3, Chinese authorities had already ordered #COVID19 virus samples destroyed, silenced Wuhan doctors, and censored public concerns online."

Hua "is right: This is a timeline the world must absolutely scrutinize," Ortagus tweeted.

Already tense relations between the two powers have worsened over the pandemic, which China has appeared to bring under control but has severely disrupted life in much of the world and infected more than 10,000 people globally.

The United States last week summoned the Chinese ambassador after another foreign ministry spokesman tweeted an unfounded conspiracy theory that the US military brought the virus to Wuhan. President Donald Trump in turn has angered Beijing by insisting on referring to SARS-CoV-2 as the "Chinese virus," a terminology discouraged by the World Health Organization.