Number 10 appeared to forget that the UK had left the EU in a tweet gaffe in which it suggested Britain was still a member of the bloc.
The official UK prime minister Twitter account, which has the handle @10DowningStreet, posted an image which said the "UK is home to twice as many AI companies as any other EU country".
It deleted the post less than an hour later and reposted it after rectifying the error.
The new version said "any EU country" rather than "any other EU country".
Twitter users who spotted the previous post before it was deleted were quick to mock the account.
"I think we all preferred the previous tweet to be honest," wrote one Twitter user, while another said: "Perhaps you can see what a terrible mistake leaving the EU has been."
The UK officially left more than three years ago at the start of 2020 after voting to leave in 2016, and the process has been beset with problems.
Increased bureaucracy has been to blame for many of the issues, with huge queues regularly forming at Dover as lorries go through additional checks to enter the EU.
Brexit has also been blamed for a breakdown of power-sharing in Northern Ireland, with the Democratic Unionist Party refusing to form a government with Sinn Fein until issues relating to the new land border with the EU can be resolved.
The tweet comparing the UK to European Union countries was highlighting the UK's investment in artificial intelligence, including £13 million for use of the technology in healthcare such as surgical robotics.
Rishi Sunak has long been enthusiastic about the opportunities of AI and wants the UK to be home to a global AI regulator.
The PM has previously spoke of the possibility of tackling “incurable diseases like cancer and dementia or new ways to grow crops”.
He believes the UK “can lead” on AI safety research “because we already have good capability in it”.
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