The party of the German Chancellor Angela Merkel has declared that its countrymen expelled by Poland after the Second World War have a ‘right to a homeland’ and said the deportations should be condemned under international law.

Wartime animosity between Poland and Germany could resurface after a new election manifesto published by the Christian Democratic Union (CDU) pledged to promote the cause of those expelled.

In 1945 millions of ethnic Germans were forced from their homes after a redrawing of the border resulted in their lands becoming part of Poland.