The leader of Germany's Social Democrats on Saturday vowed to oppose a push by Bavarian conservatives to crack down on migration, in defiance of conservative Chancellor Angela Merkel, warning the dispute could lead to a "German Brexit".
"There will be bilateral and trilateral agreements, how can we help each other, not always wait for all 28 members", she said.
"So Sunday is a first exchange with interested member states - it was open to all member states, but of course not every country is affected in the same way - no more and no less than a working and consultative meeting".
It has fuelled tensions among member states, and anti-migrant parties have won votes by playing to public fears of foreigners.
"These rescue ships can forget about reaching Italy", Italy's new firebrand interior minister, Matteo Salvini, said Saturday as he assured his anti-migrant base that he would "crush" the human trafficking business.
He said the European Union should also work more with Africa, tighten borders further and explore setting up bases outside its territory where it would decide on asylum requests before claimants make it to European Union soil, and hold them there if they were rejected.
But Italy, where a new government includes the anti-immigrant League, made clear it was not willing to play along.
On Saturday, Spain also announced it had rescued 569 more migrants at sea, many from boats in the Strait of Gibraltar, a busy shipping lane with treacherous currents.
The Lifeline "should move from its position toward their original destination to prevent escalation" of the situation, Muscat tweeted.
Chancellor Merkel is strongly opposed to Seehofer's plan and said such a unilateral move would have "a domino effect", prompting other European Union member states to push back refugees and further increase the burden of member states like Italy and Greece.
As with everything linked to migration in Europe, even the meeting in Brussels did not please everybody. What started as talks between half a dozen leaders now involves at least 16, as others demanded to take part.
If a "satisfactory" deal is not achieved at next week's summit, German Interior Minister and CSU chief Horst Seehofer has threatened to defy Merkel and turn away at the German border people who have applied for asylum in other European Union states. "Nobody is forced to attend either", said Alexander Winterstein, spokesman for the European Commission, where the talks will take place. Macron framed it in humanitarian language, saying that it's not right for those with no chance of getting asylum in Europe to die in the Mediterranean or live in "unworthy" conditions, but his proposal would mean that France follows Italy in banning entry to migrant ships.
In France, the Malian migrant Mamoudou Gassama, who climbed up to a fourth-floor balcony to save a four-year-old child in danger of falling, was granted French citizenship and time with President Macron for an act of courage - an opportunity unlikely to come the way of others seeking nationality.
The SPD has held three closed meetings, to discuss preparation for a "quick" election campaign in the event of possible re-elections according to local media.
Ironically, the tough talk comes as the number of migrants entering Europe is dropping significantly.
"We do not have a crisis of numbers". "We have lots more to do". Elaine Ganley in Paris and Stephen Calleja in Valetta, Malta, contributed.