Global stock markets experienced significant declines, mirroring a rout on Wall Street, as the Democratic victory in the US midterm elections fueled fears of a potential backlash against artificial intelligence (AI) development.

Asia saw a widespread downturn, with Japan's Nikkei 225 plunging 6%, marking its worst single-day drop since April 2025. South Korea and Taiwan's indices also fell sharply, declining more than 8% at their opening. European markets followed suit, with Germany's Dax and France's Cac indices dropping 1.7% and 1.4%, respectively. London's FTSE 100 opened 150 points lower.

The sell-off on Wall Street was substantial, with the tech-heavy Nasdaq index tumbling 5.5% and the S&P 500 index falling 4.4%. This volatility has been attributed to growing trader anxiety over potential Democratic control of Congress, which could lead to increased scrutiny and regulation of AI infrastructure development, particularly concerning data centers. Concerns about the billions invested in AI technology and the possibility of an AI bubble have contributed to the market's jitters.

"The scale of the falls in some of the market’s biggest names has been striking," said Stuart Clark, portfolio manager at Quilter. "But it also highlights the concentration risk that has built up in US equity markets. With a relatively small number of technology and semiconductor stocks now carrying so much weight, weakness in those names quickly translates into sizeable falls for the Nasdaq and S&P 500."

Wall Street's volatility index, a measure of expected market swings, surged to its highest level in seven months. Tech giants were particularly hard-hit, with shares of companies like Tesla, Nvidia, SanDisk, Advanced Micro Devices, and Micron Technology experiencing significant drops.

Former President Donald Trump attributed the market downturn to the midterm election results, stating on Truth Social, "The Stock Market crashed today because the Dumocrats had a big Tuesday — So sad to see, you only have yourselves to blame!"

While market futures indicated a mixed opening for US stocks, with some indices expected to fall further and the Nasdaq showing a small rise, the broader economic concerns and the tech sell-off continue to impact global markets. The FTSE 100, despite having less exposure to AI stocks, was not immune to the broader global economic concerns that contributed to the sell-off.

In separate market movements, oil prices rose towards $100 a barrel amid investor uncertainty regarding the potential impact of the election outcome on the Middle East conflict.