News that the lab, part of cloud division Amazon Web Services (AWS), has closed comes with AI at the forefront of a tech race between China and the United States.

In a screenshot of a WeChat post widely circulated on Chinese social media this week, Wang Minjie, a scientist at the lab, said its disbanding was "due to the strategic adjustment between China and the United States".

AWS announced job cuts across its operations last week, with some reports putting the losses at hundreds.

Amazon declined to confirm the Shanghai lab's closure directly when contacted by AFP.

"We've made the difficult business decision to eliminate some roles across particular teams in AWS," spokesman Brad Glasser said in a similar statement to the one released in response to the broader job losses.

"These decisions are necessary as we continue to invest, hire, and optimize resources to deliver innovation for our customers."

A dedicated AWS China webpage for the lab seen on Wednesday by AFP was no longer accessible on Friday.

According to an archive of the page, the lab was established in autumn 2018, with part of its remit to "actively foster collaboration with the research community".

Other US tech firms such as Microsoft and IBM have scaled back their research divisions in China recently, as the tech competition between Washington and Beijing shows no sign of abating.