Erdogan Visiting Germany in late September

The two allies of NATO's military alliance have deteriorated their relations after the Erdogan government's crackdown on opponents after a failed coup in 2016 and during the arrest of German citizens.

The spokeswoman did not say whether Erdogan would hold talks with Chancellor Angela Merkel. Merkel's office refused to comment.

The largest German newspaper “Bild” announced last month that Erdogan will visit Germany around the end of September.

A state visit would include a reception by Steinmeier with military honours and a formal state banquet. German and Turkish foreign ministers pledged earlier this year to do everything to improve relations.

Their solution led to the release in February of a German-Turkish journalist who was held in Turkey for a year for alleged security violations. His release met a key requirement from Germany, which still takes account of what it calls Turkey's worsening human rights record.

Another German national was arrested in southeastern Turkey last month charged with spreading propaganda to Turkish militants, Voa writes.

The Turkish government has cleared more than 150,000 civil servants and has arrested 77,000 people since the failed coup.

It has also launched cross-border operations in Syria against what it says are terrorist threats from the Kurdish militia and YPG, which it considers a terrorist organisation linked to the outlawed Kurdistan Workers' Party (PKK).

Turkey's human rights groups and Western allies have criticised the crackdown, saying Erdogan has used the coup as a pretext to hit opponents.