Microsoft has given up its seat as an observer on the board of ChatGPT-owner OpenAI amid fears of a crackdown by competition regulators.

The US tech giant, which has invested $13bn in the company, said in a letter to OpenAI that it would withdraw from the board “effective immediately,” according to the Financial Times.

Apple had been expected to take up a similar role as part of a landmark agreement to add ChatGPT to hundreds of millions of iPhones.

However, the world’s most-valuable company is also not expected to do so, the FT said.

It comes amid mounting pressure from competition regulators about the development of AI, which they fear could be concentrated in the hands of a few hugely wealthy companies.

European regulators said last month that they would talk to Microsoft’s rivals about OpenAI’s exclusive use of its technology.

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