Former US president Donald Trump, whose time in office was marked by tense relations in Beijing, had in January last year barred nearly all non-US citizens who were in China from entering the United States after the coronavirus outbreak.

On the Twitter-like Weibo service on Wednesday, the visa section of the US embassy in China asked students what they were waiting for after the Biden administration eased restrictions.

"Spring has come and the flowers are in bloom. Are you like this dog who can't wait to go out and play?" said the post in Chinese, which was accompanied by a video of an excited puppy trying to climb over a safety gate.

The post drew an angry backlash from some Weibo users, however, who felt the comparison was inappropriate, and was later deleted.

"Is this American humour? I believe they did it on purpose!" one user wrote.

"Dogs in American culture basically have positive meanings, but in Chinese culture and idioms, they are mostly negative," wrote another user. Others quipped that the students' "master" was now calling them back to the United States.

The Global Times, an English-language tabloid run by the Chinese Communist Party's People's Daily, also cited netizens as saying that the post was "blatant racism".

A US embassy spokesman in Beijing issued an apology on Thursday morning to anyone who had been offended by the comments.

"The social media post in question was meant to be light-hearted and humorous," he said. "We took it down immediately when we saw it was not received in the spirit we intended."

Australian Associated Press