UBS's dealmaking fees slipped by nearly 60% in the third quarter, kicking off earnings season for major European investment banks after a slump at Wall Street rivals.

The Swiss bank's dealmaking unit posted revenue of $329m over the three months, a decline of 57% on the same period last year and below analyst expectations. Its capital markets unit fell by 63% to $193m, while a 49% drop in M&A fees was sharper than most major US banks.