German Chancellor Olaf Scholz and Italian Prime Minister Giorgia will agree to greater cooperation on issues from energy to defence at an intergovernmental summit in Berlin on Wednesday, the first in seven years, according to government sources.

With Scholz from the centre-left Social Democrats and Meloni from the rightist Brothers of Italy, the two leaders and their governments make for unlikely allies.

Yet with Europe facing war on its doorstep in Ukraine, worries over illegal migration and a scramble for new sources of energy, the leaders of the euro zone's first- and third-largest economies have rallied on a number of issues of late.

These include the construction of a pipeline to transport gas and hydrogen between the two countries and approaches to tackle illegal migration.

The German stance on illegal migration has converged more with the Italian one. It has switched to a tougher stance in view of rising arrivals and complaints from local authorities that they cannot deal with the surge.

Scholz has said for example he would look closely at Italy's deal with Albania to build two reception and detention camps there for migrants arriving by sea.

Still, migration does not feature highly in the 31-page action plan obtained by Reuters that Scholz and Meloni are set to sign on Wednesday, which simply notes that the two governments should continue to liaise on the matter.

In the plan, Berlin and Rome pledge to enhance regular dialogue - for example through meetings of their defence and foreign ministers - and coordinate more closely on key policies in general.

The fact the document is a plan, and not a treaty, underscores the slightly less close alliance between Germany and Italy compared to each country with France - the euro zone's second-largest economy.

The summit on Wednesday will be preceded by a German-Italian business forum. Scholz and Meloni will also dial in separately to a meeting of G20 leaders to conclude India's presidency of the group of the world's 20 most powerful nations.

The two premiers are set to hold a news conference in the evening followed by a working dinner. The Italian government delegation is set to leave in the evening. (Reporting by Angelo Amante in Rome and Andreas Rinke and Sarah Marsh in Berlin; Editing by Nick Macfie)