German President Frank-Walter Steinmeier has asked Poland for forgiveness during Second World War commemorations.
Speaking as he attended a ceremony in the Polish city of Wielun, where the first German bombs fell 80 years ago, Mr Stenmeier said: “I bow my head before the Polish victims of Germany's tyranny. And I ask forgiveness.”
The German president, who was joined by his Polish counterpart Andrzej Duda, also condemned the “desire to annihilate” that started the conflict.
The pair attended a ceremony in Wielun in the early hours of the morning, where a minute's silence was observed.
Mr Duda, who described Nazi Germany's attack on Poland as “an act of barbarity”, said: “Wielun was to show what kind of war it would be, that it would be a total war, a war without rules, a destructive war.”
Another ceremony was set to take place on Sunday in Poland’s capital Warsaw, attended by world leaders including German Chancellor Angela Merkel and US Vice-President Mike Pence.
As commemorations started, Poland has repeated demands for compensation from Germany for the losses it suffered during the conflict.
Around six million Polish people were killed in the Second World War.
Polish Prime Minister Mateusz Morawiecki said in an interview with German media: “We have lost six million people, many more than any other country that has received vast reparations. It is not fair. It cannot be this way.”