The finance ministers of Germany and France agreed on Monday to strengthen the euro zone, giving a new impulse to stalled reforms of the currency union and warning that if they fail political extremists will take power.

Wolfgang Schaeuble and Bruno Le Maire agreed at their first meeting since the May 7 election of Emmanuel Macron as French president to set up a joint working group that would present ideas by July on deepening euro zone integration.

Le Maire said the group would look at fiscal convergence, coordinating economic policy and joint investment projects, and warned that the euro zone's two largest economies must deliver successful reform during Macron's five-year term.

"We have a responsibility to deliver results," the Frenchman said in a joint news conference with Schaeuble, noting the strong performance of far-left and far-right candidates in France's presidential election.

"This obliges us all to deliver concrete results. Because if we don't succeed the extremes will succeed us," he added, before flying together with Schaeuble to Brussels for a euro zone finance ministers' meeting.

Schaeuble added: "We both know that a central challenge for both of us as finance ministers is to make our contribution to the promotion of Europe at a time of chances but also of challenges."

"We know strengthening the monetary union is of great importance," he said, adding that Germany and France had a special leadership role in the 19-member euro zone.

With Germany's economy - Europe's largest - outperforming that of France, the traditional Franco-German engine at the heart of the EU that has often misfired in recent years.

Monday's meeting - one week after Macron met German Chancellor Angela Merkel in Berlin - was an effort to inject fresh dynamism into the partnership.

Merkel said at a separate event on Monday that Germany must help Macron to succeed to fight unemployment and added that the best way to counter euroskeptic populists was to solve problems.

Le Maire, sensitive to German concerns about France's fiscal largesse, said Paris would meet European commitments to reduce its public debt. "France will respect its European commitment to reduce deficits and we are not doing it to please the European Commission. We are doing it because it is good for France."

Turning to Britain's decision to leave the European Union, Le Maire said Brexit presents the euro zone, France and Germany with opportunities in financial markets.

"We see in Brexit the possibility for our financial sectors to be more attractive than they were in the past. This means jobs, work, and wealth for our countries," he said.

"Brexit gives us this opportunity and we intend on seizing this opportunity.”