Germany's biggest lender Deutsche Bank reported Wednesday a heavy net loss in the third quarter, as the costs of its latest phase of restructuring weigh on the bottom line.

The group lost 859 million euros ($954 million) in July-September, down from a profit of 211 million last year.

The bank also saw a pre-tax loss of 687 million euros, compared with a gain of 506 million in 2018.

And revenues fell 15 percent, to 5.3 billion.

But chief executive Christian Sewing highlighted that the so-called "core bank" of four businesses Deutsche plans to maintain into the future was profitable.

Costs related to cutting its workforce helped push Deutsche Bank into the red
Costs related to cutting its workforce helped push Deutsche Bank into the red AFP / Daniel ROLAND

Among those units, the former flagship investment bank remained the lender's problem child, with falling revenues and profits as it closed share trading activities.

Elsewhere the retail bank and asset management unit also reported falling revenues, although the corporate bank provided a bright spot of growth.

Costs grew four percent, including outlays of some 234 million euros linked to departing staff, but fell back four percent when counting out such one-off effects.

By the end of September, Deutsche had 89,958 staff, down 1,000 compared with June's figure, when it announced 18,000 -- around one-fifth of workers -- would leave.

Weighed down by both the restructuring and business headwinds, Deutsche's net losses in the year to September mounted to 3.9 billion euros.

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