* Interior minister says he has confidence in Maassen
* SPD says domestic intelligence chief must go
* Seehofer jeered in parliament as he defends Maassen (Updates with additional talks planned Tuesday)
By Andreas Rinke
BERLIN, Sept 13 (Reuters) - The leaders of Germany's ruling parties said they would meet on Tuesday to try to agree whether the embattled head of the domestic intelligence agency should keep his job, coalition sources told Reuters.
Hans-Georg Maassen, head of the Office for the Protection of the Constitution (BfV), has been under fire since a newspaper interview last week in which he questioned the authenticity of video footage showing right-wing extremists hounding migrants.
The centre-left Social Democrats (SPD), coalition partners of Chancellor Angela Merkel's conservatives, want to fire Maassen. Conservative interior minister Horst Seehofer says he sees no reason to do so.
Merkel, Seehofer and SPD leader Andrea Nahles met at the chancellery for two hours on Thursday, but agreed to maintain silence on the issue until a follow-up meeting on Tuesday afternoon, the sources said.
The debate over Maassen's future adds to tensions already plaguing Merkel's loveless coalition, which nearly split earlier this year over immigration policy.
Finance Minister Olaf Scholz, an SPD member, said Maassen had lost credibility and that consequences should follow.
"Whoever heads up a security institution in our country must enjoy full confidence and it is clear that this confidence no longer exists and there must be consequences," Scholz, a Social Democrat, told reporters.
But Seehofer, who leads Bavaria's conservative Christian Social Union (CSU), told lawmakers earlier on Thursday he had confidence in Maassen, whom he described as an opponent of right-wing radicalism.
Maassen appeared on Wednesday before the domestic affairs committee of the lower house of parliament, the Bundestag.
"He gave a convincing explanation of his actions," Seehofer said. "He convincingly refuted several conspiracy theories and he took a persuasive stand against right-wing radicalism."
The BfV denied a report by the public broadcaster ARD that said Maassen had told a lawmaker from the far-right Alternative for Germany (AfD) about parts of his agency's annual report before it was published.
Jeering and shouting could be heard from lawmakers as Seehofer mounted his defence of Maassen, whose questioning of the video's authenticity was greeted with incredulity by some politicians and reporters on the scene.
Two newspapers reported on Tuesday that Maassen had written to Seehofer saying that the video had not been falsified and that his comments had been misunderstood.
Tensions have been running high in parts of eastern Germany since the death of a German man after an altercation with two Middle Eastern refugees, which led to weeks of marching and protests that were well attended by far-right groups. (Reporting by Michelle Martin and Thomas Escritt; Editing by Paul Carrel and Alison Williams)
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