Turkish President Recep Tayyip Erdoğan has described the Dutch as "Nazi remnants and fascists" in an escalating row over pro-Erdoğan demonstrations in the Netherlands.

It was the second time the far-right leader made the slur in the space of a week, first directed at Germany, after the Dutch government withdrew landing permission for Turkey's Foreign Minister Mevlüt Çavuşoğlu.

More from IBTimes UK

Çavuşoğlu was due to speak at a rally in Rotterdam on Saturday (11 March), but Germany and the Netherlands have resisted pro-Erdoğan demonstrations in their countries, claiming they are a security threat.

The rallies are in support of a 16 April referendum on constitutional reforms, which if decided in Erdoğan's way, would give him greater powers following last year's failed coup attempt.

In a statement, Dutch Prime Minister Mark Rutte said he tried to solve the row with Turkey diplomatically, but Erdoğan has taken the more vocal approach.

"They do not know politics or international diplomacy… these Nazi remnants, they are fascists," he said at a rally in Istanbul, reported the Guardian, as the crowd booed in response.

"Ban our foreign minister from flying however much you like, but from now on, let's see how your flights will land in Turkey," he added.

When Erdoğan first made his Nazi remarks, Germany hit out angrily and said that there are "lines that must not be crossed".

However, in repeating the rhetoric, he has demonstrated he is willing to risk international relationships in order to garner support at home in order to pass the constitutional measures.

In his statement, Rutte tried to clarify that his opposition to the rallies was not out of a repulsion to democracy – as claimed by Erdoğan – but because they did not comply with local regulations.

"Many Dutch people with a Turkish background are authorised to vote in the referendum over the Turkish constitution. The Dutch government does not have any protest against gatherings in our country to inform them about it," he said.

"But these gatherings may not contribute to tensions in our society and everyone who wants to hold a gathering is obliged to follow instructions of those in authority so that public order and safety can be guaranteed."