At issue is one measure in a 63-point action plan by Interior Minister Horst Seehofer -one that would instruct border police to turn back migrants found to have applied for asylum in other countries of the European Union's border-free area.
German Chancellor Angela Merkel was fighting Tuesday (12 June) to stamp out the first major row within her uneasy coalition, as disputes over her refugee policy returned to haunt her while she negotiates a broad European Union asylum deal. But that would also lead to the collapse of her government, which has been in power for less than 100 days, and would nearly inevitably end her chancellorship.
Chancellor Merkel will most likely have discussions over the weekend to find a solution and reach a last-minute compromise with the CSU.
"What's important to me is that we make these decisions together in Europe, and not act unilaterally", she said at a Berlin press conference alongside Austrian Chancellor Sebastian Kurz, where she stressed the need to better secure the bloc's external borders. Markus Söder, the minister president of Bavaria and a leading member of the CSU, said: "Why will we achieve something in two weeks that was not possible in three years?" referring to the refugee crisis of summer 2015.
Austria, a major transit nation on the migrants' route, and Italy rejected the argument this week, however, saying they supported Mr. Seehofer's initiative.
Mr Seehofer, of the Christian Social Union (CSU), has often voiced his hostility towards Mrs Merkel's open border policy, which brought more than a million refugees in the country in 2015.
Other members of Merkel's government turned to name-calling Friday, with Andrea Nahles, the leader of Germany's center-left Social Democrats, accusing Soeder of "behaving like a bonsai Trump".
She has pledged instead to seek bilateral agreements with arrival and transit countries and a wider solution by the European Union, which holds its next summit on June 28-29, while admitting that this plan is "ambitious".
At the meeting, CSU lawmakers said they could not wait that long.
In a highly unusual move, a session of the lower house, the Bundestag, was interrupted to allow the CDU and the CSU to meet separately on the issue. Horst Seehofer - who is in all likelihood grandstanding ahead of regional elections in Bavaria - appears to have, in the words of one commentator, got Mrs Merkel's back against the wall.
Chancellor Angela Merkel says Germany is committed to the North Atlantic Treaty Organisation target of spending 2 percent of a country's gross domestic product on defense, but is realistic about reaching it.
Germany's finance minister, a Social Democrat, seemed to suggest that further intrigue within the coalition could end in a bloodbath.
At their meeting in Paris, Macron and Conte also demanded "profound" changes to the EU's asylum rules which put the migrant burden on their port of entry to Europe - mainly Italy and Greece. However, the issue is costing her support within the CDU and is a growing source of tension within her conservative bloc.