Merkel thanked on Thursday volunteers, full-time helpers, police, soldiers as well as the staff of German authorities for their "overwhelming and truly moving wave of spontaneous helpfulness" amid the refugee wave.

Looking to 2016, the German leader said "there is no question that the influx of so many people will keep demanding much of us. It will take time, energy and money."

But she recalled that her country had mastered many big challenges in the past such as reunification a quarter-century ago and benefited from a "robust and innovative" economy.

In order to achieve a successful integration, German people should learn from the mistakes of the past, Merkel noted. "Our values, our traditions, our sense of justice, our language, our laws, our rules," she added, apply "to all who wish to live here."

In the end, the chancellor repeated her famous attitude toward the refugee crisis: "We can do it, because Germany is a strong country."

"I am convinced that, if handled properly, today's great task presented by the influx and the integration of so many people is an opportunity for tomorrow," she said.