Chancellor Angela Merkel's office hit back Monday at Turkish President Recep Tayyip Erdogan in a blistering row over a German parliamentary vote declaring the Ottoman Empire committed genocide against Armenians.

Erdogan has angrily condemned last week's vote on the World War I massacres, charging that the 11 German MPs with Turkish roots who backed it supported "terrorism" by the banned Kurdish Workers' Party (PKK), and demanding Sunday that they undergo "blood tests" to see "what kind of Turks they are".

Joachim Gauck made his name as a human rights activist under communism and later restored the relevance of the president's ceremonial office with bold stands on the refugee crisis and Germany's growing role on the world stage.

Gauck, 76, who announced Monday that he would not stand for a second term next year due to his advanced age, looks back on a remarkable biography that parallels his country's tumultuous history.

German President Joachim Gauck said Monday that he would not stand for a second term, creating a political headache for Chancellor Angela Merkel ahead of an election year.

The popular Gauck, 76, who has held the largely ceremonial post of head of state since 2012, made the announcement at Berlin's Bellevue Palace, citing his advanced age.

A German right-wing populist politician has attacked Chancellor Angela Merkel as a "dictator" who is trying to "replace the German people" with migrants, a Sunday newspaper reported.

Alexander Gauland, of the anti-immigration Alternative for Germany (AfD) party, told a rally outside Berlin that Merkel's liberal asylum policy was radically transforming the face of the country, the Frankfurter Allgemeine Sonntagszeitung said.

German Chancellor Angela Merkel agrees with her party that the massacre of Armenians by Ottoman forces should be branded a genocide but will not attend a parliament vote Thursday on the issue, her spokeswoman said.

"She told me this morning that she sided with her parliamentary group," her spokeswoman Christiane Wirtz told journalists, when asked if Merkel signaled her approval of the Armenian "genocide" resolution during a party meeting on Wednesday.

Germany expects up to 100,000 undocumented migrants to leave the country in 2016, a number Interior Minister Thomas de Maiziere Wednesday hailed as high but insufficient after last year's record influx.

"If the current trend continues then we will reach a total of between 90,000 and 100,000 deportations and voluntary returns," de Maiziere told reporters.

Germany's parliament votes Thursday on a resolution that brands the massacre of Armenians by Ottoman forces as genocide, drawing a clear warning from Turkey's president that it would harm ties.

Four people died and several more were injured in southern Germany after violent storms with torrential rains caused severe flooding, authorities said on Monday.

One of those killed was a 13-year-old girl who was hit by a train Sunday while seeking shelter from the rains under a railway bridge.

Turkey on Monday strongly warned the German parliament against adopting a resolution recognizing the mass killings of Armenians under the Ottoman Empire as genocide, saying it could have repercussions for bilateral ties.

The German lower house of parliament is set to vote on Thursday on the resolution over the two years of slaughter from 1915, which carries the contested word "genocide" throughout the text.

A leading member of the right-wing populist Alternative for Germany (AfD) party sparked outrage Sunday after making racist remarks about national football team defender Jerome Boateng.

AfD's deputy chief Alexander Gauland told the Sunday newspaper Frankfurter Allgemeine Sonntagszeitung that Germans would not like to have Boateng, who has a Ghanaian father and was born and brought up in Berlin, as a neighbor.