"No special EU summit is planned. The convocation of such a summit would be up to the institutions" of the European Union, the spokesman said.

"Obviously the German government is holding discussions in this context with different members states and the [EU] Commission," he added.

The Bild newspaper had reported earlier on Sunday that Merkel was planning to discuss solutions to the crisis with Greece, Italy, Austria and other countries, ahead of an EU summit scheduled for June 28-29.

The report came amid a public row between Merkel and German Interior Minister Horst Seehofer over his plans to toughen Germany's stance on migration and tighten border controls.

Merkel's current stance is to seek an EU-level solution to illegal immigration at the summit in Brussels at the end of the month, and has asked for patience.

But Seehofer, who leads the Christian Social Union - the Bavarian sister party of Merkel's Christian Democrats - has threatened to bypass the chancellor in order to push through his plans to deport illegal migrants at the German border.

In a separate Bild report, the minister denied that he was trying to split the conservative bloc.

"Nobody in the CSU is interested in toppling the chancellor, dissolving the CDU/CSU partnership or blowing up the coalition," Seehofer said.

"We want to finally find a sustainable solution to the rejection of immigrants from our borders," he added.

Seehofer is a vocal critic of Merkel's decision to open Germany's borders to hundreds of thousands of asylum seekers in 2015.

Dissatisfaction with the decision led to an erosion of support for the traditional conservative parties and a surge for the right-wing populist Alternative for Germany (AfD), which won 94 of the 709 seats in parliament in last year's elections.

Australian Associated Press