Frankfurt am Main — Germany's biggest lender, Deutsche Bank, said on Wednesday that it had only a "limited role" in relation to Danske Bank's dirty-money scandal, as a correspondent bank handling foreign transactions.

That role meant Deutsche was "in the second line, not in charge of checking the clients," compliance chief Sylvie Matherat said at a Frankfurt banking conference.

Investigators in Copenhagen, Brussels, London and the US are probing transactions at Danske relating to about 15,000 foreign clients who dealt with its Estonian branch.

A total of 9.5-million such payments totalling €200bn passed through the unit between 2007 and 2015, with a significant proportion of them under suspicion.

When handling transactions on behalf of another institution, "controls are limited because you don't have access to their client base", Matherat said.

Deutsche did still carry out some checks, she insisted.

"On our side, we look at the transactions coming from that [client] bank and when you fear something is wrong you must file a ‘suspicious’ report. That's what we do."

Deutsche worked with Danske for eight years, Matherat confirmed, before ending the relationship in 2015 after suspect activities were uncovered at the Danish firm.

She added that as a correspondent bank, Deutsche carries out transactions amounting to “between 450-billion and 500-billion [worldwide] in terms of dollars only” each day, contrasting that figure with the $150bn of suspicious transactions over eight years at Danske.

So far Deutsche has not been targeted in any probe, although the powerful US Securities and Exchange Commission (SEC) and department of justice are reportedly eyeing the Danske scandal closely.

For its part, the German bank said on Tuesday that it was not aware of any investigation by local financial authorities targeting it.