BERLIN: France and Germany on Tuesday will celebrate 50 years since a landmark treaty sealed their post-war reconciliation aiming to paper over nagging differences between Europe's two powerhouse neighbours.

French President Francois Hollande arrived in the snowy German capital late on Monday to join Chancellor Angela Merkel for a hectic line-up of events to fete the Elysee Treaty, inked in 1963 when both were eight years old.

Eighteen years after the end of World War II, then French president Charles de Gaulle and West German chancellor Konrad Adenauer formalised on January 22 the cooperation that has since been at the heart of European unity.

Both countries' governments are due to gather at the chancellery, while lawmakers from France's National Assembly will also join their Bundestag counterparts for a two-hour debate in the historic Reichstag building.

Merkel and Hollande are scheduled to give a joint press conference.

The day wraps up with a concert at the Berlin Philharmonic hall, including music by Beethoven and French composer Camille Saint-Saens.

After Hollande's arrival in Berlin, he and Merkel sought to present a unified front during a televised debate with about 200 German and French youth, despite tensions from the euro crisis which has propelled Berlin into Europe's driving seat.

On military matters too, Paris and Berlin have limited cooperation, as the current crisis in Mali and Germany's non-intervention in Libya in 2011, have shown, but Merkel sought to play down their differences.

“Step by step we will always weigh up, can we do that, or can't we...,” she said, insisting that Germany would not leave its partner high and dry.

While French troops are fighting alongside Malian forces against Islamist militants in the West African state, Germany has pledged two military transport planes and one million euros ($1.3 million) in humanitarian aid.

For his part, Hollande welcomed Germany's “immediate” support on Mali.

The two leaders have differed on the best approach for stemming the eurozone turbulence – with Hollande pushing for fresh spending to bolster growth, while Merkel's pro-austerity mantra made her a detested figure in struggling EU member states but has gone down well among German voters.

Even if the two have pulled off compromises, Germany, which has fared far better in the crisis than many of its partners, has expressed hopes the French economy will return to robust growth.

Hollande recognised that his country had a “problem of competitiveness”, saying Germany – Europe's effective paymaster – had “made efforts” while France “has lost time”.

For her part, Merkel said there was no one model of economic development, even though the exporting might of Germany is often cited as an example.