Germany's Parliament speaker has criticized Turkish President Recep Tayyip Erdogan for his broadside against German lawmakers of Turkish origin after the legislature labeled the killings of Armenians by Ottoman Turks a century ago "genocide."

Turkey withdrew its ambassador for consultations after the German Parliament's vote last week. Erdogan derided German lawmakers of Turkish origin who supported the resolution, saying they should be given blood tests to prove whether they are really Turkish. Several have reported receiving threats.

Speaker Norbert Lammert told Parliament Thursday: "I would not have thought it possible that, in the 21st century, a democratically elected president would link his criticism of democratically elected German Parliament lawmakers with doubts about their Turkish origins and describe their blood as tainted."

Chancellor Angela Merkel has called the Turkish comments "incomprehensible."