Steinmeier said on Tuesday that groups such as the Kurdistan Workers' Party (PKK) were banned in Germany.
"The PKK and other extremist parties are banned as terrorist groups here. They are criminally prosecuted," the German foreign minister said, adding, "That is why I cannot understand the comments made about Germany today in Turkey."
Turkish Foreign Minister Mevlut Cavusoglu accused Germany on Tuesday of being the country offering the highest level of support to the leftist militant group of the Revolutionary People's Liberation Party-Front, also known as the DHKP-C, and the PKK, which has staged armed attacks against Turkey.
"Germany is the country that supports terrorist organizations against Turkey the most," Cavusoglu said in the Turkish capital Ankara. "The DHKP-C and PKK are carrying out activities in Germany, but they support those because they are against Turkey."
On Monday, Kurds based in Germany gathered in front of the parliament building in the capital Berlin, protesting the "suppressive" policies of Turkish President Recep Tayyip Erdogan as well as the German government's relations with Ankara.
The participants in the demonstration held up flags of Kurdish groups, including the People's Protection Units, also known as the YPG, and the Women’s Protection Units, also known as the YPJ, which are fighting Takfiri militancy in Syria and Iraq.
Ankara considers the Kurdish groups to be affiliated with the PKK, which has been fighting for an independent Kurdish state inside Turkey since 1984.
Relations between Ankara and Berlin soured in June, when the German parliament passed a resolution, recognizing the Armenian "genocide" at the hands of Ottoman Turks during World War I.
Some 250 German troops are stationed at the Incirlik airbase in Turkey, along with six Tornado reconnaissance jets and a refueling plane, as part of the so-called US-led coalition allegedly fighting the Takfiri Daesh terrorists group in Syria and Iraq.
Ankara has stirred tensions in its relations with Berlin by denying German parliamentarians access to the airbase, Press TV reported.
219