Chinese firm DeepSeek's artificial intelligence chatbot has soared to the top of the Apple Store's download charts, stunning industry insiders and analysts with its ability to match its US competitors at a lower cost.

The programme has shaken up the tech industry and hit US titans including Nvidia and Meta, which has spent vast sums of cash to get ahead in the fast-developing AI sector.

Nasdaq futures slumped and technology shares slid in Japan on Monday as surging popularity of DeepSeek's product wobbled investors' faith in the profitability of AI and the sector's voracious demand for high-tech chips.

DeepSeek has rolled out a free assistant it says uses lower-cost chips and less data, seemingly challenging a widespread bet in financial markets that AI will drive demand along a supply chain from chipmakers to data centres.

"It's a case of a crowded trade, and now DeepSeek is giving a reason for investors and traders to unwind," said Wong Kok Hoong, head of equity sales trading at Maybank.

AI-focused startup investor SoftBank Group slid more than eight percent, on course for its biggest one-day fall since September 30.

Last week it announced a US$19 billion commitment to fund Stargate, a data-centre joint venture with OpenAI. (Agencies)