Turkish President Recep Tayyip Erdogan has warned the Netherlands it will “pay the price” for harming ties after two of his ministers were barred.
Mr Erdogan said: “We will teach them international diplomacy.”
The two ministers were blocked from addressing Turkish expatriates in Rotterdam on Saturday, with one of them escorted to the German border.
The Dutch government says such events would stoke tensions days before the Netherlands’ general election.
The ministers were trying to win support among expatriate voters for a referendum on expanding Turkish presidential powers.
Fatma Betul Sayan Kaya, Turkey’s family minister, had arrived by road on Saturday but was denied entry to the consulate in Rotterdam and was taken to the German border by Dutch police.
Foreign Minister Mevlut Cavusoglu tried to fly in but was refused entry.
Water cannon and riot police on horseback were deployed to disperse about 1,000 people protesting outside the Turkish consulate in Rotterdam overnight.
Protests were also held on Sunday outside the Dutch consulate in Istanbul, where the Netherlands’ flag was replaced with a Turkish one, which was later removed.
The Netherlands’ foreign ministry responded by saying that the Turkish authorities were responsible for the safety of Dutch diplomats in Turkey.
Speaking at an awards ceremony in Istanbul on Sunday, Mr Erdogan said of the Netherlands: “They will certainly pay the price, and also learn what diplomacy is.”
Accusing the Dutch of acting in an “impudent” way, he said: “Holland! If you are sacrificing Turkish-Dutch relations for the sake of the elections on Wednesday, you will pay a price.”
Threatening to travel to rallies abroad himself, he added: “The West has clearly shown its true face in the last couple of days. What we have seen… is a clear manifestations of Islamophobia.
“I have said that I had thought that Nazism was over, but that I was wrong. Nazism is alive in the West,” he said.
But he thanked France for allowing Mr Cavusoglu to travel to the northern city of Metz to address a rally there on Sunday, saying: “France was not deceived by such games.”
A French official has said the rally had been allowed because it did not pose a public order threat, while France’s foreign ministry has called on Turkey to avoid provocations.
Speaking in Metz, Mr Cavusoglu described the Netherlands as the “capital of fascism”.
He said of the Dutch ambassador, who is on leave: “We are saying that there is no need to come back to Turkey. He can’t come, he can’t enter.”
Ms Kaya also vented her anger at the Dutch after flying back to Istanbul from Cologne.
She said: “We were subjected to rude and rough treatment… Treating a female minister this way is very ugly.”
Dutch PM Mark Rutte said Mr Erdogan’s comment on Saturday that the Dutch were “Nazi remnants and fascists” was “unacceptable”.
He said it was “wrong” for Turkey to send ministers to the Netherlands, despite the Dutch government warning that it could inflame tensions in society.
He said Turkey had threatened sanctions and “we can never do business under this kind of blackmail”.
“We drew a red line,” he said.
The Dutch government is facing a severe electoral challenge from the anti-Islam party of Geert Wilders in its election on Wednesday.
Reports say the owner of a venue in the Swedish capital, Stockholm, has now cancelled a pro-Erdogan rally on Sunday that was to have been attended by Turkey’s agriculture minister. Sweden’s foreign ministry said it was not involved in the decision and that the event can take place elsewhere.
What is the row about?
Turkey is holding a referendum on 16 April on whether to turn from a parliamentary to a presidential republic, more akin to the United States.
If successful, it would give sweeping new powers to the president, allowing him or her to appoint ministers, prepare the budget, choose the majority of senior judges and enact certain laws by decree.
What’s more, the president alone would be able to announce a state of emergency and dismiss parliament.
In order to get it passed, Mr Erdogan needs the votes of citizens living within Turkey and abroad.
There are 5.5 million Turks living outside the country, with 1.4 million eligible voters in Germany alone – and the Yes campaign is keen to get them on side.
So a number of rallies have been planned for countries with large numbers of expat voters, including Germany, Austria and the Netherlands.
However, Mr Erdogan’s supporters have found themselves blocked from holding these rallies.
Why are countries trying to prevent the rallies?
Many of the countries, including Germany, have cited security concerns as the official reason.
Austrian Foreign Minister Sebastian Kurz said Mr Erdogan was not welcome to hold rallies as this could increase friction and hinder integration.
Many European nations have also expressed deep disquiet about Turkey’s response to the July coup attempt and the country’s perceived slide towards authoritarianism under President Erdogan.
Germany in particular has been critical of the mass arrests and purges that followed – with nearly 100,000 civil servants removed from their posts.