France allowed Turkey’s Foreign Minister Mevlut Cavusoglu to speak at a pro-government rally in the eastern town of Metz on March 12 after Germany, and the Netherlands blocked similar public gatherings in their cities, triggering diplomatic rows.

“In the absence of a proven threat to public order, there was no reason to prohibit the meeting,” French Foreign Minister Jean- Marc Ayrault said in a statement, according to Reuters.

France, one of the EU’s heavyweights with strong commercial ties with Turkey, called for a de-escalation of the diplomatic spat between Ankara and several European countries over the referendum rallies.

Meanwhile, Danish Prime Minister Lars Lokke Rasmussen has asked his Turkish counterpart Binali Yildirim to postpone a visit to Denmark.

“Under normal circumstances it would be a pleasure for me to greet Yildirim in Copenhagen…But with the current rhetorical attacks by Turkey against the Netherlands, a new meeting cannot be seen isolated from that,” Rasmussen said in a statement posted on Facebook.

“The characterisation of the Western democracies and the current rhetorical attacks against the Netherlands by Turkey means that a meeting right now would be interpreted as if Denmark is viewing developments in Turkey more mildly, which is not at all the case,” the Danish PM added.

Meanwhile, German Finance Minister Wolfgang Schaeuble said on March 12 that it was difficult to continue working with Turkey on economic aid because of the row over the Turkish ministers’ rallies in Europe.

"We don't want to escalate it, everyone in the German government is agreed, we only want Turkey to return to reason,” Schauble told Germany’s public broadcaster ZDF, according to Reuters.

However, some observers think that the latest diplomatic spat with Europe could help the Turkish ruling party AKP win the upcoming referendum. The tensions with several European countries could increase President Tayyip Erdogan’s popularity with Turkey’s nationalist voters and boost his image of a strong leader standing against the West.

“Nazism is alive in the West,” Erdogan said on March 12 in a rally in Istanbul. “The Netherlands, that acted like a banana republic, will pay a price for its actions,” he scolded, calling on international organisations to impose sanctions against the Netherlands.

Turkish PM Yildirim also warned that Turkey would retaliate in the harshest ways. But he did not say how.

The opposition leader Kemal Kilicdaroglu, Erdogan’s main rival, has called on the government to suspend relations with the Netherlands.