BERLIN (Reuters) - Germany has rejected calls for Turkey's Prime Minister Tayyip Erdogan to cancel his visit to Cologne on Saturday, when he is due to address almost 20,000 supporters in what could amount to a de facto rally for Turkey's presidential poll in August.
Erdogan has not yet said whether he will run for the Turkish president, but he is widely expected to do so.
Although his party says the Cologne speech is not a campaign event, some German lawmakers have urged Berlin to discourage it, owing to Erdogan's pugnacious style and what critics say are his increasing authoritarian tendencies.
One leading Christian Democrat, Julia Kloeckner, urged Turks living in Germany to boycott the event to protest Erdogan's reaction to a mining disaster in Turkey last week that killed 301 people. His stance sparked angry protests in Turkey.
German government spokesman Steffen Seibert said the visit was a private one and the Turkish premier was welcome. But he added: "The government expects Prime Minister Erdogan to approach this appearance with responsibility and sensitivity."
Foreign Minister Frank-Walter Steinmeier said he expected the speech to be "appropriate to international customs and above all fitting to the close nature of German-Turkish ties".
Erdogan's fiery, patriotic speeches to Turkish audiences in Germany have frequently caused controversy. In 2008, he told them not to assimilate and called for Turkish-language schools.
Turkey's presidents have until now been chosen by parliament and played a largely ceremonial role. August's election will be the first direct vote for the post, which Erdogan wants to carry more power.
An estimated 2 million Turkish citizens living in Germany have a right to vote in Turkish elections, and Erdogan would want their support if he stands. Another 1 million people of Turkish origin have become German citizens.
"In theory, we are a country which is open to visitors," said Peter Tauber, the secretary general of the Christian Democrats, Chancellor Angela Merkel's party. "Everyone can speak here and we have freedom of speech and freedom to gather."
However, those rights did not exist everywhere, he said, including in Turkey.
Over the past year, Erdogan has weathered anti-government protests, a corruption scandal and a feud with an influential Islamic preacher he accuses of trying to unseat him. His two-week closure of social networking site Twitter and a block on access to video-sharing platform YouTube earlier this year drew criticism at home and abroad, including the German government.
Yet he still remains hugely popular among Turkey's poorer and more religious voters.
(Reporting by Alexandra Hudson, Andreas Rinke and Hans-Edzard Busemann; Editing by Stephen Brown, Larry King)