Angela Merkel’s prickly Bavarian allies have stepped up their campaign against the German chancellor, likening her divisive migration policy to a “reign of injustice”.
Bavarian premier Horst Seehofer's choice of words carry a deliberate sting, using language German politicians usually reserve for the defunct East Berlin regime of Erich Honecker.
For Dr Merkel, raised in East Germany, being compared to the deceased communist leader and his vanished state is the latest in a long line of insults aimed at the Christian Democratic Union (CDU) leader from her Bavarian allies, the ruling Christian Social Union (CSU).
Bavarians in Germany’s south have found themselves on the front lines of a European migration crisis of historic proportions, one that saw Germany accept 1.1 million asylum seekers last year.
In recent months Mr Seehofer and his state government in Munich have warned Berlin they cannot cope with another million people this year.
The standoff dates to last summer, when Dr Merkel allowed Syrians trapped in Hungary travel to Germany, instructing immigration officials not to apply EU migration rules to Syrian asylum seekers.
Though those rules have been reinstated, and Berlin is in the process of agreeing a tough new asylum regime, Bavarian leaders want an asylum cap and tighter border checks.
"At the moment we don't have a system of law and order. It is reign of injustice," said Mr Seehofer to a Bavarian regional newspaper, a week after he irritated Merkel officials by meeting Russian president Vladimir Putin in Moscow.
As well as verbal and diplomatic slights, the CSU has threatened to challenge Berlin’s migration policy at the German constitutional court.
If Dr Merkel fails to secure fairer EU burden-sharing in Brussels next week, Mr Seehofer has warned Dr Merkel that he will make good on his threat and go to the Karlsruhe court in March.
While the CDU refused to react to the CSU leader’s provocation, their Social Democratic Party coalition allies have watched the escalating CDU-CSU row with amusement, with some questioning Mr Seehofer’s mental health.
CSU officials backed their boss yesterday, insisting Dr Merkel's migration shift last August and September was illegal and irresponsible for encouraging millions of additional asylum seekers to western Europe.
As Germany’s grand coalition approaches its halfway mark, and with three state elections next month, no one in Berlin is interested in early federal elections.
But senior SPD leaders fear that further CSU sabre-rattling in Bavaria could have unintended consequences and trigger a rupture in Berlin.
"Horst Seehofer's . . . malicious choice of words will only crank up further the crisis in the CDU/CSU," said Thomas Oppermann, Bundestag floor leader.