Barclays investment bankers posted a record quarter despite a 40% slump in fixed income trading revenues as fees surged during an ongoing deal boom.

Profits within the UK lender's investment bank were up by 51% to £1bn, with fees from mergers and acquisitions advice up by 160%. Fees across its traditional investment banking business increased by 19% to £873m during the second quarter — a new high for Barclays.