Italy's economy minister, Giovanni Tria, also cancelled a meeting with his counterpart in Paris, a day after French President Emmanuel Macron said Rome had acted with "cynicism and irresponsibility" by closing its ports to migrants.
Macron's office said Tuesday that France doesn't want to "start a precedent" that would allow some European countries to breach worldwide laws and rely on other EU member states to take in migrants.
United Nations refugee chief Filippo Grandi urged the European Union on Wednesday to sort out its "shameful" refugee policy after both Italy and Malta turned away a ship carrying hundreds of migrants.
Sophie Beau said Wednesday in a news conference in Marseille, France, "it's a relief for everyone, our teams and of course above all for the survivors to know that they are finally allowed to head to a safe port in Europe".
The Aquarius, carrying no fewer than 600 rescued sea migrants, was turned away from Italian ports on Sunday, as the Rome government suggested Malta should instead take it in. Foreign Ministry spokeswoman Agnes von der Muhll saying it was "fully aware of the burden that the migration pressure is placing on Italy" and that it was committed to cooperating with Rome on immigration.
The chancellor said migration represented a significant challenge for Europe when it was in a "very fragile situation". Some countries feel justified in stopping migrants from entering when they should have registered elsewhere.
Ms Merkel spoke after Interior Minister Horst Seehofer, a top CSU leader, called for Germany to ally itself with Austria, governed by a right-wing coalition, and Italy on migration and security policies. He declared his support for Kurz's proposal for a three-way "axis of the willing" with Italy to fight illegal migration.
Speaking to the senate Salvini said "he hoped for an official apology as soon as possible", from France.
Salvini, who last week said he would not allow Italy to become Europe's "refugee camp", told the Senate he was open to a possible "axis" with Germany and Austria ahead of a key European Union summit at the end of June that will consider possible changes to asylum law to better share the burden of incoming migrants.
He demanded that France move from "words to action and offer a sign of generosity" by taking more in.
Salvini has accused European aid groups of essentially operating taxi services for Libya-based human traffickers, and has said Italy will now refuse them entry. Meanwhile, an Italian coast guard ship with more than 900 migrants on board has docked this morning in the Sicilian port of Catania. "The coastguard and navy can continue to save lives, but other countries need to keep giving us a hand", he said.