Chancellor Angela Merkel is being pressed by the German Federation of Expellees to decide on a controversial museum that will depict refugees' post-War experiences, despite a potential backlash from Warsaw.

The focus of Poland's ire is the federation's president and a member of Merkel's Christian Democratic Union, Erika Steinbach, who it perceives as the strident voice of an organisation associated with Nazism and the German occupation "and one who will push an anti-Polish agenda.

"There is a coalition agreement [between Germany and Poland] to create a visible symbol against expulsions, and there is a law that should now put everything in place," said Gesine Schwan, the opposition Social Democrats' presidential candidate and chief coordinator for German-Polish relations in Berlin.

However, Schwann warned on Wednesday, if Steinbach is made a leading figure on the museum project, Polish fears that it will become a biased "centre against expulsion" could derail trust and add further resentment to an already strained relationship.

The expulsion of German citizens from Eastern lands started when the Red Army entered Poland in 1944.