A diplomatic rift between Turkey and key European nations deepened Sunday as President Recep Tayyip Erdogan accused Germany of "Nazi practices," days after a local authority prevented a Turkish minister from addressing a rally.
Over at an election campaign event in Amsterdam, meanwhile, Dutch right-wing populist Geert Wilders also resorted to extreme-right comparisons, calling Mr. Erdogan an "Islamo-fascist leader."
The diplomatic tensions have been rising in recent days amid Turkish plans to have government ministers to address rallies in Germany and the Netherlands in support of an upcoming constitutional referendum that would give Erdogan new powers.
Speaking in Istanbul, the Turkish president fanned the flames with a stinging verbal attack.
"In Germany, they are not allowing our friends to speak. Let them do so. Do you think that by not allowing them to speak the votes in Germany will come out 'no' instead of 'yes?'" Erdogan said. "Germany, you don't have anything to do with democracy. These current practices of yours are no different than the Nazi practices of the past."
On Thursday, Turkey's justice minister canceled a meeting with his German counterpart after local authorities in southwest Germany withdrew permission for him to use a venue to hold a rally near the French border that was part of a campaign to get Turks in Germany to vote "yes" in the referendum.
Turkey's economy minister, Nihat Zeybekci, was due to speak at two events in western Germany on Sunday. There are about 1.4 million people in Germany who are eligible to vote in the Turkish referendum.
Julia Kloeckner, a deputy leader of Merkel's Christian Democratic Union, told the German daily Bild that Erdogan's Nazi comparison was "a new pinnacle of immoderation."
"Mr. Erdogan is reacting like a stubborn child who can't get his own way," she told the paper.
Austrian Chancellor Christian Kern, in an interview with the German newspaper Welt am Sonntag, said it's time to pull the plug on long-stalled moves to bring Turkey into the 28-nation EU.
"We shouldn't just temporarily suspend the accession talks with Turkey but end them," Ms. Kern said. "We can't continue to negotiate about membership with a country that has been steadily distancing itself for years, during ongoing access talks, from democratic standards and principles of the rule of law."
The Dutch government is investigating whether it can halt a rally being planned for later in the week at which Turkish Foreign Minister Mevlut Cavusoglu is reportedly due to speak.
Prime Minister Mark Rutte told Dutch broadcaster NOS on Saturday that his government "is looking at all legal avenues to prevent such a visit." Mr. Rutte said the proposed constitutional changes take Turkey, an aspirant European Union member state, "in a less democratic direction."
"We believe that Dutch public space is not the place for political campaigns of other countries," Rutte wrote earlier on his Facebook page.
Kern urged "a concerted approach by the EU to prevent such campaign appearances," saying then specific countries like Germany would not come under pressure from Turkey.
Wilders, whose Party for Freedom is lagging only slightly behind Rutte's VVD party in polls before the Dutch March 15 election for parliament's lower house, said he would go further if he were in power.
"I think that coming here to advocate a change of the Turkish constitution that will only strengthen the Islamo-fascist leader Erdogan of Turkey more than Parliament, Turkish parliament, is the worst thing that could happen to us," Wilders told reporters at a campaign event.
Wilders said if he were the Dutch prime minister, "''I would call the whole cabinet of Turkey 'persona non grata' for a month or two, not allowing them to come here."
Kern, however, pointed out that totally cutting ties with Ankara wouldn't be in EU interests. An EU migrant deal with Turkey, which also is a NATO member, has significantly cut down the number of migrants crossing into Europe.
"We should realign the relationship, without the illusion of EU membership," Kern said. "Turkey is an important partner in security matters, on migration and on economic cooperation. Turkey has stuck to all of its commitments resulting from the refugee deal, in any case. We should build upon that."
Associated Press reporters Frank Jordans in Berlin and Cinar Kiper in Istanbul contributed to this report.