The Dutch government denied landing rights to Turkey's top diplomat Mevlut Cavusoglu on Saturday, shortly after the minister threatened sanctions against the Netherlands should he be blocked from entering the country to stage a rally.
The Dutch government said allowing Cavusoglu to hold a political rally at the Turkish consulate in Rotterdam posed a security risk, and that the threat of sanctions had "made the search for a sensible solution impossible".
"If Holland cancels my flight clearance ... we could impose very heavy economic and political sanctions against Holland," Cavusoglu told CNN Turk earlier in the day.
A constitutional referendum in Turkey, scheduled for April 16, would significantly expand the powers of Erdogan, who has been conducting a widespread purge of government critics since a failed military coup in July.
Dutch Prime Minister Mark Rutte said late Friday that, although his government did not want Turkish ministers to campaign in the Netherlands, it did not have the power to cancel events taking place at the consulates of other countries.
"That is Turkish soil - the territory of the Turkish government, but we will be strict about public order and safety" at the event, Rutte told Dutch broadcaster NOS late Friday.
Turkey is at odds with several European countries about its efforts to promote constitutional changes among members of the large Turkish diaspora community. Many events have been blocked on security concerns. Beyond that, Turkish law prohibits campaigning abroad, even though that rule is frequently ignored.
The proposed reforms have caused concern both among domestic opponents and among Turkey watchers around the world.
Turkey risks installing a "one-person regime" under the proposed constitutional reforms, experts in the Council of Europe warned this week.
Ín addition to his foreign minister's threat of sanctions, Erdogan said Saturday that Ankara could block Dutch diplomats from entering his country.
"From now on, let's see how your planes come to Turkey," said Erdogan, according to a transcript from state-run Anadolu news agency, adding that the Dutch authorities were "remnants of Nazis" and "fascists."
Cavusoglu held crisis talks with his German counterpart, Sigmar Gabriel, this week in an effort to mend relations after a series of bans on campaign rallies prompted a diplomatic row.