Commerzbank is advising shareholders with Bank of Scotland and Halifax stock to hold on to it while merger talks are continuing. The brokers advise that if the deal is completed there could be further upside for investors in these shares but cautions there is still a considerable risk that it will not happen.

In a new report, Commerzbank says the deal looks sensible and presents revenue synergies that could add £4 billion sterling (€6.4 billion) to shareholder value. The deal would bring together the UK retail banking and bancassurance strengths of Halifax with the Scottish business banking expertise of Bank of Scotland.

The areas of overlap are limited so cost savings should not be a major factor with revenue synergies a more important element.