National Bank says it will write off the $165million value of its investment in Maple Financial Group, which operates Maple Bank in Germany.

Maple Bank's business activities were suspended during the weekend by Germany's Financial Supervisory Authority, following investigations into certain trading activities during the 2006-2010 taxation years.

The Montreal-based bank owns 24.9 per cent of Maple Financial.

National said none of its employees was involved in the trading "nor to our knowledge is National Bank of Canada or any of our employees the subject of these investigations."

It says the write off of its Maple investment will be recorded in the first quarter of fiscal 2016.