Lazard's core mergers and acquisitions advisory business failed to keep pace with booming deal activity for the second quarter running after revenues in the division fell by almost a fifth between April and June and dragged down group profits.

The value of deal advisory fees at the group run by veteran Wall Street dealmaker Bruce Wasserstein fell 17% to $164m (€120m) in the three months to the end of June, compared with the equivalent period last year.