Morgan Stanley has displaced Citigroup at the top of the European mergers and acquisitions rankings table after Iberdrola, the Spanish utilities company, launched its formal £11.6bn (€17.1bn) offer for UK rival Scottish Power.

Morgan Stanley is lead adviser to Scottish Power and is now ranked number one in European M&A after advising on €387bn ($509m) worth of deals in a record year for buyout activity, according to Thomson Financial, the investment banking data provider.