Turkish Prime Minister Tayyip Erdogan has accused Germany in a newspaper interview of letting Turkey down by not doing more to support its European Union membership bid and failing to recognise Turks' efforts to integrate in German society.

The interview appeared in Wednesday's edition of the mass-circulation paper Bild, hours before Erdogan meets Chancellor Angela Merkel in Berlin for a ceremony commemorating the 50th anniversary of the labour pact which brought large numbers of Turkish workers to Germany.

Ties between the two leaders are strained because of Merkel's deep reservations about Turkey joining the EU, and Erdogan's speeches to the Turkish community on previous trips to Germany, in which he urged Turks not to forget their roots.

Asked what he considered German politicians' biggest failing over integration, Erdogan said: German politicians do not acknowledge enough the integration of the three million Turks in Germany.

Germany should do much more for Turkey's EU membership bid as this would massively support integration. Because we Turks regard Germany very positively, we feel very let down on this issue, he added.

Instead of full membership Merkel favours a privileged partnership for Turkey, whose 74 million people are predominantly Muslim.

Describing Turks as open and loyal, Erdogan said Germany should show much more solidarity with Turkey. He also criticised Germany's opposition to dual citizenship and laws which oblige any Turks moving to Germany to speak good German before arrival, saying this infringed their human rights.

If a young Turkish man loves a woman in Turkey and wants to marry her, this is seen as a mistake, as Germany demands that she first learn German. But what is the language of love? he said.

It cannot be that the love of young people is only allowed to exist in German by decree.

(Reporting by Alexandra Hudson; Editing by Tim Pearce)