Berlin/Paris - German Chancellor Angela Merkel and French President Nicolas Sarkozy stepped up their call for next month's summit of the world's most powerful economies to agree to concrete measures for overhauling the global financial sector.

In a joint letter ahead of the Group of 20 (G20) richest and emerging economies' summit in London, Merkel and Sarkozy said the meeting needed to produce "concrete results for reinforcing international financial regulation" and to draw up an action plan aimed at strengthening the role of global financial institutions.

The letter, which was sent to European Commission president Jose Barroso and Czech Prime Minister Mirek Topolanek followed signs of deep divisions within the G20 over how to address the world's biggest economic downturn since the Great Depression.

The Czech Republic currently holds the European Union's rotating six-months presidency.

While Japan has joined the US in pressing for governments to take further urgent measures to ward off the recession through boosting government spending, Merkel and Sarkozy have both ruled out another round of economic stimulus packages.

Instead, the German and French leaders have emphasized the need for restructuring the world financial system. (dpa)