Frank-Walter Steinmeier, who normally stands above the fray of day-to-day politics, urged Ms Merkel’s CDU and her CSU allies to resolve their differences over migration policy, which have flared up in recent months and threatened the stability of the coalition.
The president said the two parties, long-term allies since 1949, were “so implacably and with such boundless rigidity, like there’s no tomorrow, over problems that are actually not that intractable”.
It comes after Volker Kauder, a senior MP in Ms Merkel’s CDU, told German television that talks between the two sides on Tuesday had ended at an impasse, suggesting differences could be insurmountable.
“It is very serious – we saw that in the talks, this is not about something small, it is about something central and important. We need to talk to each other,” Mr Kauder said.
The bitter row is mostly over whether to turn away refugees and migrants at Germany’s borders if they have already registered in another EU country. Ms Merkel’s interior minister, Horst Seehofer, wants to unilaterally push ahead with the plan, but the chancellor reportedly believes any change in policy must be coordinated at an EU level.
Alexander Dobrindt, a senior CSU politician, upped the pressure on the chancellery and warned that “from the next week” the Bavarian party wanted migrants to be rejected at the border if they have already registered in another European country”.
He added: “I do not understand talking about possible future solutions for Europe while not being prepared to do what Germany can do now.”
The issue of migration was subject to emergency talks between EU member states in Brussels on Sunday, with the subject also set to get an airing at a major European Council summit on Thursday and Friday.
The CSU, the more conservative Bavaria-only sister party of the CDU, has regional elections coming up in the autumn and worries it will lose seats to the far-right AfD, which made gains in Bundestag elections last year.
Bavaria is also in Germany’s southeast, putting it on a major migration route for people travelling to the country by foot.
Under Germany’s constitution, Mr Seehofer can unilaterally push ahead with the plan because it comes within his purview – but Ms Merkel would be expected to fire him for defying her and breaching the government’s line. Were that to happen the CSU could potentially withdraw from the coalition, a scenario which would likely lead to the collapse of the government and fresh election.
Though the number of refugees and migrants travelling to Europe has fallen dramatically in the past year, the issue has rocketed up the political agenda in a number of countries after gains for far-right parties.
The threat of the AfD to establishment parties in Germany has been mirrored or surpassed by the election of the far-right League in Italy to a coalition government, and the FPOE to the Austrian governing coalition.
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