"We should no longer support immigration by people who are totally foreign to our cultural tradition, in fact we ought to block it," Alexander Gauland told Berlin's Tagesspiegel newspaper.
"There are cultural traditions that have a very hard time integrating here ... those cultural traditions are at home in the Middle East," Gauland said.
He added that there was a danger of "parallel societies" developing in Germany "with which we won't be able to cope with in the end."
And he continued his push to bring AfD closer to anti-Islam movement Pegida by describing it as a “people's movement” comparable with the early anti-nuclear demonstrations that helped launch the Green party.
The majority of Pegida participants were not racists, but “completely normal people," he said.
Gauland, a 73-year-old from Saxony, is seen as the voice of the growing nationalist-conservative wing of AfD, which originally began as a movement almost exclusively campaigning against the Euro single currency.
He believes that mainstream centre-right party the Christian Democratic Union (CDU) will soon find itself in difficulty over Chancellor Angela Merkel's declaration that “Islam belongs to Germany” - and that his party will be there to pick up its lost voters.
“The Chancellor's words were deadly for ordinary CDU members”, Gauland said.
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