German Chancellor Angela Merkel pledged on Monday to "tangibly" stem a massive refugee influx to quell a rebellion in her conservative ranks but firmly rebuffed calls to slam the door shut.

German Chancellor Angela Merkel pledged on Monday to "tangibly" stem a massive refugee influx to quell a rebellion in her conservative ranks but firmly rebuffed calls to slam the door shut.

At a pivotal party congress of her Christian Democratic Union (CDU), Merkel said Germany would pursue a range of measures to stanch the flow of asylum seekers, slated to number around one million people this year.

But after weeks of damaging infighting in which the right wing of the party demanded an upper limit on newcomers, Merkel insisted Germany would continue to live up to its "humanitarian responsibilities".

"We want to tangibly reduce the number of refugees arriving," Merkel said.

"With an approach focused on the German, European and global level, we will succeed in regulating and limiting migration."

However she said Germany had a "moral and political" duty as Europe's top economic power to continue to help the world's desperate people, particularly those from war-ravaged Syria.

Ahead of an EU summit this week, Merkel said she was banking on a multi-pronged approach to cut refugee numbers, urging bolstered protection for the bloc's external borders, support for Turkey to host refugees long-term, and a long-shot bid for a distribution scheme among EU member states.

She also touted a range of measures already undertaken in Germany including extending a list of safe countries of origin, expediting repatriation of rejected asylum seekers and beefing up staffing to process applicants.