European equities closed at a record high on Tuesday, with the STOXX 600 index poised for its strongest quarterly performance since October 2020. The pan-European benchmark rose 0.6% to 639.77 points, lifting its quarterly gain to 9.7% across three consecutive monthly advances. Renewed enthusiasm for artificial intelligence investments and easing geopolitical tensions in the Middle East fueled the rally.

Technology shares led the charge, climbing 1.7% and tracking their best quarterly performance since October 2001. Semiconductor equipment maker ASML jumped 3.33%, while STMicroelectronics and Infineon rose 3.0% and 2.7% respectively, reflecting sustained demand for AI infrastructure. The sector is also set to outperform US technology peers over both monthly and quarterly periods.

Siemens Energy extended its gains by 5% after reaffirming strong demand for AI-related equipment in its quarterly update. Meanwhile, Abivax surged more than 20% in healthcare after announcing positive topline results from its obefazimod clinical study, lifting the broader sector by 0.9%.

Oil prices retreating to pre-conflict levels eased energy cost concerns across Europe, providing additional support for the market rally. With AI momentum showing staying power and geopolitical risks receding, European equities appear positioned for continued strength into year-end.