Germany's lower house of parliament, countering increasing anti-immigrant sentiment, declared on Friday that German culture is defined by freedom and humanity and said more should be done to integrate an influx of migrants.

More than one million migrants - mainly Muslims - flocked to Germany from the Middle East, Africa and elsewhere in 2015-16 and many Germans see integrating the newcomers as the country's biggest challenge.

Parliament's "Culture Builds Bridges" declaration comes amid a rise in support for the anti-immigrant Alternative for Germany (AfD) party, which is expected to gain seats in the Bundestag (lower house) in next year's federal election.

The declaration described Germany as a "European cultural nation" shaped by the values of the Enlightenment, freedom and humanity, and said the constitution, which states that human dignity is inviolable, defined modern German culture.

The proposal was brought by Chancellor Angela Merkel's conservative bloc in parliament and the Social Democrats (SPD), their junior partner in the ruling coalition, which have lost support to the AfD as hostility against migrants has risen.

"We want to preserve our country's rich cultural heritage, which is characterized by the diversity of its citizens, states and regions as well as by its lively art and cultural scene," the declaration said.

It said German culture encompassed seeing different lifestyles, values, religions and world views as enriching.

"That's the opposite of a culture of isolation and intolerance like that being propagated by right-wing populist movements at the moment," it said.

The Bundestag said that even migrants who only stay in Germany for a short time should be encouraged to learn the language and take part in German cultural life and media.

It urged an expansion of cultural and integration programs for migrants, volunteer training and activities such as visiting museums, theaters or libraries.