Twitter is becoming the platform of choice for Chinese diplomats abroad to promote Beijing's views and defend its position on controversial issues, despite the social media platform being blocked in China itself.
But their messages, while supported by some netizens, are often met with acerbic pushback from analysts, human rights advocates and even officials, suggesting limitations to the new communication strategy.
The latest verbal dust-up came to a head on Sunday, when former United States national security adviser Susan Rice called Chinese diplomat Zhao Lijian a "racist disgrace" after he posted and promoted a series of tweets on America's social and political issues, including racial segregation in Washington, gun violence and misogyny.
Mr Zhao, China's second-highest ranking diplomat in Pakistan, had been making the broader point, in his defence of China's internment of Uighur Muslims in Xinjiang, that the US had no right to criticise China's policies, given its history of racism and human rights abuses.
His storm of tweets was sparked by two letters last week - one from 22 countries, mostly Western apart from Japan, calling on China to close its internment camps, and a counter-letter from 37 countries with closer ties to China, backing its mass detention policy.
Mr Zhao wrote that white people hardly went to Washington's majority black and Latino south-west district, saying: "There's a saying, 'black in and white out', which means that as long as a black family enters, white people will quit and the price of the apartment will fall sharply."
South-east Washington, which Mr Zhao had been referring to, is one of the capital's poorest areas despite rising gentrification in recent years, and is often stereotyped as a hotbed of crime.
Ms Rice responded by saying that Mr Zhao should be removed from his post and recalled to China, adding: "You are a racist disgrace. And shockingly ignorant too."
Mr Zhao hit back by calling her racist and ignorant as well, though he later deleted the tweets.
The Twitter fight came days after another frosty episode over Taiwanese independence, sparked by Taiwanese President Tsai Ing-wen's visit to the US last week, which angered Beijing.
Chinese Ambassador to the US Cui Tiankai wrote last Friday that Taiwan was part of China, adding: "No attempts to split China will ever succeed. Those who play with fire will only get themselves burned. Period."
His sharply worded post stood in contrast to his very first post on Twitter early last week. Mr Cui and the Chinese Embassy in the US had both opened Twitter accounts on July 8 to "engage in more frequent and productive dialogue with Americans".
In the wake of both episodes, China experts publicly wondered whether the pattern of Chinese diplomats engaging on Twitter over sensitive issues suggested a concerted push by Beijing to increase its presence on the social media platform.
US-based China watcher Bill Bishop, who runs the Sinocism daily newsletter, said on Twitter: "Are we seeing the PRC (People's Republic of China) diplomats start to personally take the propaganda war to Twitter en masse?"
