Lawyer Michael-Hubertus von Sprenger told the German ZDF public broadcaster that Erdogan intended to press his case to Germany's highest court if necessary.

"If I'm mandated to take the case, then I'll proceed through to the end," Sprenger said, adding that Erdogan wanted to get Böhmermann "back on the right path, to produce satire and not gross insults."

Time out for Böhmermann's show

In an open letter published by the German weekly "Die Zeit," some 70 artists and prominent persons have demanded that proceedings be dropped.

Signatories include German actors Matthias Brandt and Katja Riemann, and former Greek finance minister Yanis Varoufakis.

A diplomatic wrangle - intertwined with a EU-Turkey deal on refugees - has unfolded since March 31, when Böhmermann directed a sexually crude poem at Turkey's authoritarian president on "Neo Magazin Royale," a satire show he hosts on one of ZDF's channels aimed at young adults.

Erdogan pursuing two charges

Prosecutors in Mainz, where ZDF is based, said Erdogan was pressing charges both for being insulted as a private person and as a foreign head of state.

The federal government says it is still evaluating Erdogan's request for prosecution.

Should German authorities decide to pursue prosecution, the private case could result in a one-year prison sentence while insulting a foreign head of state can be punished by up to five years in jail.

"Discussion about and criticism over Jan Böhmermann's Erdogan poem belong on the cultural pages of this country's [press] and not in court chambers in Mainz," said the open letter's 70 signatories.

Next satire how canceled

The Cologne production firm bildundtonfabrik, Böhmermann and ZDF announced on Tuesday that they had decided not to produce Thursday's edition of "Neo Magazin Royal."

Böhmermann himself was placed under police protection over concerns linked to past attacks on artists exercising their right to freedom of expression.

Böhmermann's chances 'good'

Klaus Staeck, the former president of the Berlin Academy of Arts, told Deutschlandfunk public radio on Tuesday that during his career he had successfully defended himself 41 times against attempts to ban his works.

"Everyone has the right to take a matter to court, but not to come with a Kalashnikov," Staeck said, adding that Böhmermann's chances of acquittal were "good" because judges in Germany tend to issue "opinion-friendly" verdicts.

Staeck: Böhmermann's legal chances are 'good'

Michael Bertrams, a former Constitutional Court president, urged the federal government not to authorize a head-of-state prosecution sought by Erdogan.

"[The government] would surrender not only Jan Böhmermann but also the freedoms of opinion and artistic expression to an autocrat and despot who flouts civil rights in his own country in a gross manner," said Bertram.

Thorsten Schäfer-Gümbel, deputy leader of the Social Democratic Party, said the federal government should dismiss Erdogan's complaint.

"Satire is a part of political culture of our country and a part of political life in open societies," he said. "That must be defended."

Berlin to make the call

The Social Democrats also called for the law on insulting foreign leaders to be scrapped, describing it as "antiquated" and limiting to freedom of speech.

However, the chancellor's spokesman said on Tuesday that Berlin would "not shy away" from the Böhmermann case.

"The decision will be made," even if the law is scrapped, Steffen Seibert said.

Seibert also denied claims from Ankara that Chancellor Merkel was planning a trip to Turkey to open a new refugee camp on the Syrian border.

"I have been asked a half dozen times in the last days and weeks about this trip on April 16 and never confirmed this trip, this appointment, and that is still the case," Seibert told reporters.

ipj/sms (dpa, Reuters, AFP)