Turkish President Recep Tayyip Erdogan blasted Germany on Sunday, March 5 for blocking rallies in support of him ahead of an April vote on boosting his powers, likening it to Nazi practices, AFP reports.

The attack came a day after German Chancellor called Turkish Prime Minister Binali Yildirim to try to defuse the row, which is severely straining ties between the NATO allies.

A number of local authorities in Germany have banned rallies ahead of an April 16 referendum on whether to approve changes to the constitution.

"Germany, you are not even close to democracy," Erdogan told a women's rally in Istanbul. "Your practices are not different from the Nazi practices of the past," he said.

"I thought it's been a long time since Germany left (Nazi practices). We are mistaken," he said.

Several German towns prevented appearances by Erdogan's ministers last week, citing security and safety concerns.

The cancellations have infuriated the Turkish government, which accused Berlin of working against the "Yes" campaign in the referendum and summoned the German ambassador to the foreign ministry in protest.

Chancellor Merkel called the Turkish premier on Saturday and the two countries' foreign ministers are set to meet later this week.

Germany is home to the biggest population of Turks outside Turkey with around three million in the country of Turkish origin, the legacy of a massive "guest worker" programme in the 1960s-70s.