Investment banking fees at JPMorgan slipped by 47% during the third quarter, kicking off what is expected to be a difficult reporting season for Wall Street banks' dealmaking teams.

The US lender posted profit within its corporate and investment bank of $3.5bn during the third quarter, a decline of 37% on the same period last year. Overall net income of $9.7bn for the period was ahead of analyst expectations, but down 17% on the previous year.