ROTTERDAM, Netherlands — Turkey and the Netherlands sharply escalated a dispute between the two NATO allies on Saturday as the Dutch blocked a campaign visit by the Turkish foreign minister, prompting Turkish President Recep Tayyip Erdogan to call them “fascists.”

The Netherlands withdrew the landing permission for Foreign Minister Mevlut Cavusoglu because of objections to his intention to rally in Rotterdam for a Turkish referendum on constitutional reforms to expand presidential powers, which the Dutch see as a step backward from democracy.

“They do not know politics or international diplomacy,” Erdogan told a rally in Istanbul. “These Nazi remnants, they are fascists,” he added, as the crowd booed.

Dutch Prime Minister Mark Rutte called it “a crazy remark, of course. But I understand they are angry but this is of course way out of line.”

Erdogan told a rally in Istanbul: “You can stop our foreign minister’s plane all you want, let’s see how your (diplomatic) planes will come to Turkey from now on.” Cavusoglu also referred to possible sanctions, and Rutte said consultations under such threats were impossible, forcing him to bar the visit.

The government said it withdrew the permission because of “risks to public order and security,” causing Cavusoglu to say: “so is the foreign minister of the Turkish republic a terrorist?”

He added that “we will give them the response they deserve.”

Cavusoglu, who was speaking at Istanbul’s airport, didn’t say where his next European destination was. French authorities say he’s scheduled to travel to the northern city of Metz on Sunday. Turkish officials have been campaigning in various European cities before the April 16 referendum.

Around 100 people marched in Istanbul to protest the Dutch decision, with demonstrators placing a black wreath in front of the Dutch Consulate amid a heavy police presence.

At dusk in Rotterdam, about 100 pro-Turkish demonstrators had gathered outside the Turkish Consulate with flags in a peaceful protest following the acrimonious words between both governments.

The state-run Anadolu news agency said the Family and Social Policies Minister decided to go to Rotterdam via road from Germany, but police closed off the road in front of the Turkish consul-general’s residency. Dutch authorities couldn’t immediately confirm the information.