Maitland takes on the brief this week in the wake of reports suggesting Commerz-bank has made huge losses in derivatives trading.
While the Frankfurt-headquartered bank categorically denies the reports, the rumours have frayed investors' nerves and sparked a ten per cent plunge in its share price.
The appointment marks the first time Commerzbank has hired a City agency on a brief of this size and scope. Commerzbank head of press Peter Peitsch said: 'No other mandate of this kind exists with Commerzbank.
'Maitland's appointment has to do with all the rumours that have spread over the last few weeks - we see these rumours originating in London and it's natural that we look for a company like this for the brief,' he added.
Maitland partners Duncan Campbell-Smith and Philip Gawith head the brief, reporting to Commerzbank executive vice-president of corporate communications Ulrich Ramm and chief executive Klaus-Peter Muller.
The consultancy will handle Commerzbank's international PR via partners in New York, Paris and Germany, although Campbell-Smith said they will not handle the bank's domestic German PR.
Maitland's appointment has led the agency to resign its account with UK fund manager New Star Asset Management. Commerzbank has a troubled relationship with New Star founder John Duffield, since the sale of his former firm, Jupiter Asset Management, to the German bank two years ago.