The Turkish foreign ministry has rejected a call by top EU officials to show restraint in a row with the Netherlands over political campaigning.
It described as “worthless” an appeal by EU foreign policy chief Federica Mogherini and EU Enlargement Commissioner Johannes Hahn.
The row erupted after the Dutch barred Turkish ministers from campaigning among expatriates for a referendum.
The referendum would controversially boost the Turkish president’s powers.
In response to the Dutch move, Turkey barred the Dutch ambassador from returning to Ankara and suspended high-level political talks, while Turkish President Recep Tayyip Erdogan accused the Dutch of using Nazi tactics.
The Dutch government cited “risks to public order and security” as reasons for blocking the Turkish rallies.
Voters in the Netherlands go to the polls on Wednesday for a general election dominated by concerns about immigration and Islamic radicalism.
Relations between the EU and Turkey, a predominantly Muslim country regarded as crucial to tackling Europe’s migrant crisis, have long been strained.
Turkey’s foreign ministry said it was “grave” of the EU to stand by the Netherlands.
On Monday, Ms Mogherini and Mr Hahn had called on Turkey to “refrain from excessive statements and actions that risk further exacerbating the situation”.
However, responding to the diplomatic sanctions announced by Turkey, Dutch Prime Minister Mark Rutte said they were “not too bad”.
Why did the Dutch ban the Turkish rallies?
Rallies were called to encourage Turkey’s large expatriate communities in the EU to vote Yes in a referendum on 16 April on expanding the president’s powers.
Some 5.5 million Turks live outside the country, including an estimated 400,000 in the Netherlands.
The Dutch authorities barred two Turkish cabinet ministers from addressing crowds in the city of Rotterdam, with Minister of Family Affairs Fatma Betul Sayan Kaya escorted to the German border after entering the Netherlands by land.
Prime Minister Rutte said the city authorities had feared an armed clash between Ms Kaya’s security detail and local police.
While the Dutch position was that the rallies posed a threat to public order, the EU has made very clear its unease over the Turkish referendum itself.
In their statement on Monday, Ms Mogherini and Mr Hahn voiced concern that it could lead to an “excessive concentration of powers in one office”.
Media captionA look at how tensions between Turkey and the Netherlands unfolded
How high are passions in this row?
Mr Erdogan likened the Netherlands to “a banana republic”, demanded international organisations impose sanctions on the country and accused countries in the West of “Islamophobia”.
“I have said that I had thought that Nazism was over, but I was wrong,” he said.
Mr Rutte said Mr Erdogan’s comment that the Dutch were “Nazi remnants” was “unacceptable”, and demanded an apology.
The Netherlands was invaded by Nazi Germany in 1940 and occupied right up until the final days of World War Two in Europe, in May 1945. Rotterdam was devastated by German bombing during the invasion.
Could there be wider repercussions?
Turkish officials have also suggested reconsidering part of the deal with the EU to stem the flow of undocumented migrants.
The number of migrants reaching Greece by sea dropped sharply after the deal was reached in March of last year.
Turkey is also a candidate to join the EU but negotiations have made little headway over the last decade.
As a Nato state bordering Syria, it is also a vital partner in the campaign to fight so-called Islamic State.
A note on terminology: The BBC uses the term migrant to refer to all people on the move who have yet to complete the legal process of claiming asylum. This group includes people fleeing war-torn countries such as Syria, who are likely to be granted refugee status, as well as people who are seeking jobs and better lives, who governments are likely to rule are economic migrants.