Turkey’s president has accused Germany of “mercilessly supporting terrorism” - the latest in a string of insults traded between Ankara and its Nato allies in northern Europe.

Recep Tayyip Erdogan’s comments, broadcast live on television, threaten to inflame an already volatile diplomatic crisis that erupted at the weekend when the Netherlands blocked Turkish ministers from speaking at a political rally in Rotterdam.

On Saturday, Mr Erdogan branded the Netherlands "Nazi remnants, fascists" after the Dutch government withdrew permission for his Foreign Minister to land there.

Chancellor Angela Merkel responded that Germany “completely rejects rhetorical and any other comparisons with the National Socialists made by the Turkish president”.

“These comparisons are completely misguided,” she said. “They trivialise the suffering.

“Particularly in the Netherlands that endured so much agony through the National Socialists, it's just completely unacceptable.

“That's why the Netherlands can count on my complete support and solidarity on this."

Angela Merkel tells Turkey to stop comparing Germany to the Nazis

Mr Erdogan’s latest attack on Germany appears to come in response to Ms Merkel’s rebuttal, and at a time when the increasingly authoritarian leader is seeking support from Turks in a referendum on boosting his powers.

It also comes as Turkey is caught up by its own terrorism problem, with militant attacks and the war in neighbouring Syria.

Mr Erdogan has previously accused European countries, including Germany, of harbouring terrorists, something European countries deny.

The Turkish president also said he planned to take the spat with the Netherlands to the European Court of Human Rights.

The dispute threatens to harm Turkey's already fragile bid to join the EU.