DeepSeek, a Hangzhou-based startup founded in 2023, shot to the top of Apple’s App Store free app chart after releasing a new open-source AI model it says rivals OpenAI's work. Its website was hit by outages amid a spike in interest.

The Chinese artificial intelligence firm DeepSeek has rattled markets with claims its latest AI model performs on a par with those of OpenAI, despite using less advanced, more energy efficient computer chips.

Some AI researchers hailed DeepSeek’s R1 as a breakthrough on the same level as DeepMind’s AlphaZero, a 2017 model that became superhuman at the board games Chess and Go by purely playing against itself and improving, rather than observing any human games.