Berlin police said they had stopped a parade of Turkish fans ahead of the EURO quarter-final match between the Netherlands and Turkey, as fans made mass gestures with the sign of the Turkish far-right group "Grey Wolves".

"During the Turkish fan parade, the Gray Wolves salute was made en masse. For this reason, the police stopped the march and called on the fans to stop with that sign," wrote the Berlin police on platform X, adding that the fan march "is not the place for political messages".

The match between the Netherlands and Turkey tonight at 21:00 at the Olympic Stadium in Berlin, where the president of Turkey, Recep Tayyip Erdogan, should also participate, comes at the height of the diplomatic dispute between Berlin and Ankara.

The "Grey Wolves" gesture, three fingers joined with the index finger and little finger raised in the air to draw the profile of a wolf, is in the spotlight this week as the sign was made by Turkish defender Merih Demiral to celebrate goals which he scored in the 1/8 match against Austria. Because of this, Demiral was suspended for two matches by UEFA's decision.

Demiral's gesture also caused diplomatic tensions between Turkey and Germany. Turkey summoned the German ambassador to Ankara for talks on Wednesday in protest at a statement by German Interior Minister Nancy Feser, who called the player's gesture "unacceptable".

Germany responded the next day by calling the Turkish ambassador in Berlin. Erdogan did not react directly, but several ministers and a spokesman for his Justice and Development Party (AKP) condemned the UEFA investigation and the German minister's response.

The Gray Wolves are classified as a right-wing extremist group with 18,500 to 20,000 members in Germany, making them the second largest right-wing extremist organization, according to German intelligence.

Extremism experts say the Gray Wolves' worldview is deeply nationalist and Islamist, with hatred for Kurds, Jews, Christians, Armenians, Greeks, the EU and the US. The group, which has a long history of terrorism dating back to the 1970s, has been blamed for bombings in Paris and Bangkok and the assassination of Pope John Paul II.