BERLIN (Reuters) - German Chancellor Angela Merkel’s coalition will change the rules for the ceremonial post of doyen of parliament after it emerged that an anti-immigrant party member might qualify for it later this year.

A general view shows Germany's Bundestag (lower house of parliament) before the first round of voting during the German presidential election at the Reichstag in Berlin, February 12, 2017. REUTERS/Fabrizio Bensch

Wilhelm von Gottberg, a member of the Alternative for Germany (AfD) who turns 77 on Thursday, would be the oldest member of the Bundestag lower house if the right-wing party wins seats for the first time in a Sept. 24 national election.

Current rules would give him the honorary title of “Alterspraesident” (president by seniority) and allow him to open the first session of parliament and make a speech.

But Merkel’s conservative bloc and the Social Democrats (SPD), their junior coalition partner, decided on Tuesday that the post should be given to the longest-serving deputy rather than the oldest one, said Volker Kauder, the conservatives’ parliamentary floor leader.

Senior SPD politician Thomas Oppermann said: “The inaugural meeting should be led by an experienced member of parliament, irrespective of which party the person is a member of.”

The changes to the rules for the role of parliament’s doyen, which has in the past been held by noted German politicians such as Willy Brandt, are due to be agreed in April.

Gottberg once wrote that the Holocaust was used as an “effective tool to criminalize Germans and their history” and said German refugees pushed out of eastern Europe after World War Two should have the right of return.

Kauder denied suggestions that the decision was taken because Gottberg is an AfD member, saying it was “a development of the rules we’ve had up until now”.

Finance Minister Wolfgang Schaeuble, a veteran conservative, is the longest-serving member of parliament. A Bundestag deputy since 1972, he is running again in September’s election.

AfD deputy leader Alexander Gauland criticized the decision, saying: “The other parties must be very scared of the AfD to already be resorting to such tricks purely to prevent us from being able to provide the president by seniority in the next German Bundestag.”

The latest Forsa and Allensbach polls show support for the AfD at 7 percent, its weakest level in those polls since November 2015. Bitter infighting, a drop in migrant arrivals and the nomination of charismatic SPD chancellor candidate Martin Schulz - who looks like a fresh alternative to Merkel - have hurt its fortunes.

All the other parties have said they will not form a coalition with the AfD.

The AfD has been rocked by scandal this year with senior member Bjoern Hoecke calling Berlin’s Holocaust Memorial a “monument of shame” and denying Adolf Hitler was “absolutely evil”. Reports have also circulated of another senior AfD member selling medals from the Nazi era featuring swastikas.