Germany’s Angela Merkel called for a spirit of compromise on reforming the euro zone at a meeting on Thursday with French President Emmanuel Macron, who pressed for solidarity among members of the currency union, Reuters reported.

Before their talks, the two said they would present a united front at June meeting of European Union leaders on a range of issues including reform of the 19-member euro zone, which Merkel said they agreed was “not yet sufficiently crisis-proof”.

France and Germany, which account for around 50 percent of euro zone output, are essential to the reform drive.

Stressing the need for compromise, Merkel said: “We each bring some different facets but I think the sum of our proposals will make for a good result in the end.”

However, their meeting took place against a backdrop of grumbling by lawmakers from Merkel’s conservative bloc, wary that Macron’s call for more solidarity could see German taxpayers’ money used to fund profligate member states.

“No monetary union can exist without elements of convergence,” the French leader said.