Chancellor Angela Merkel spoke after Wednesday's 10th National Integration summit in Berlin.
Merkel voiced skepticism after the meeting at a mooted "axis of the willing" between Germany, Austria and Italy to combat illegal migration. "It's about [finding] a European solution," she said.
She noted that several countries besides Italy, Germany and Austria — not least Spain and Greece — were also on the front lines of EU migration.
"Therefore I believe that there should be many such forms of cooperation. In other words, not just this one direction, but many more if we want to reach a common European solution to the questions of illegal migration, but also on forms of legal migration."
Merkel had met with Austrian Chancellor Sebastian Kurz to discuss, among other issues, migration. Seehofer also met with Kurz, who was visiting Berlin.
Interior Minister Seehofer absent
The place of Interior Minister Horst Seehofer at Wednesday's summit in Berlin was taken by Marco Wanderwitz, a CDU member and deputy minister in Seehofer's interior ministry.
Seehofer, of the Bavarian Christian Social Union (CSU), gave no reason for his absence but his differences with Merkel over migration policy have been particularly visible since his new "migration master plan," a 63-point document on migration and asylum rules, was postponed rather than published on Tuesday.
The former Bavarian premier is the first federal interior minister in office not to attend the summit which has been held regularly since July 2006. His brief includes responsibility for migration and integration policy. He had been scheduled to speak on "Values and Cohesion."
Integration Commissioner Annette Widmann-Mauz expressed disappointment that Seehofer did not attend, but said she looked forward to close cooperation within the National Action Plan for Integration (Nationalen Aktionsplans Integration).
Merkel and Seehofer at odds over migration
Merkel and Seehofer had met earlier in the week and apparently been unable to reconcile their differences over migration.
Seehofer wants to see people without the necessary entry papers turned away at the German border. Merkel wants to find a European solution to illegal migration, involving enhanced controls around the EU's external borders.
Seehofer and Italy's Salvini
After refusing a ship managed by an NGO with 600 migrants permission to dock in Italy, Interior Minister Matteo Salvini, who is also head of the conservative League (Liga) party, said he and Seehofer would jointly present a plan to protect the EU's borders.
Italian officials said the two ministers were in "full agreement" on security and immigration and would act "with the aim of wasting no more time." Salvini also said he expected to meet Seehofer in Berlin shortly.
jm/msh (dpa, Reuters)