Angela Merkel was due to take part in a church service Saturday in the city of Duisburg for the 21 victims of last week's fatal crush at the Love Parade dance music festival, DPA reported.
Duisburg football stadium, space for up to 25,000 mourners has been made available to watch a live broadcast of the memorial service, which is taking place at the Salvatorkirche in the city.
The access tunnel to the festival grounds where the crush occurred on July 24 as party-goers attempted to gain entry to the massive event has been sealed off, and crowd control measures have been erected around the church.
President Christian Wulff is also due to join some 500 mourners inside the church for the ecumenical service, along with relatives of the dead and injured. More than 500 people were hurt in the crush.
Duisburg's mayor, Adolf Sauerland, is not expected to attend the ceremony, as in recent days calls for his resignation have grown.