Turkish President Recep Tayyip Erdogan has accused Germany of "Nazi practices" for blocking his ministers from speaking

Turkish President Recep Tayyip Erdogan on Monday accused German Chancellor Angela Merkel of "supporting terrorists", in a spiralling row with EU states after the blocking of poll rallies by ministers.

"Mrs Merkel, why are you hiding terrorists in your country?... Why are you not doing anything?" Erdogan said in an interview with A-Haber television, accusing Berlin of not responding to 4,500 dossiers sent by Ankara on terror suspects.

"Mrs Merkel, you are supporting terrorists," he added.

Erdogan said Germany, which Turkey has long accused of harbouring Kurdish militants and wanted suspects from the failed July 15 coup, was "giving support to terror in a ruthless way".

He also lambasted Merkel for her public backing of Dutch Prime Minister Mark Rutte in the diplomatic crisis sparked by The Hague's refusal to let Turkish ministers hold rallies in the country ahead of an April 16 referendum on expanding Erdogan's powers.

German authorities had also last week blocked rallies from taking place, infuriating Ankara.

Referring to the developments across Europe in recent days, Erdogan reiterated his controversial comparison with the Third Reich.

"Nazism, we can call this Neo-nazism. A new Nazism tendency," he said.