Some officials have described the European summit as a moment of reckoning for the common currency, under siege by Europe's burgeoning debt crisis. Before the meeting, there remained a divergence of opinion on exactly how to resolve the two-year debt contagion that threatens the stability of the world economy.

US President Barack Obama told reporters in Washington that Europe is prosperous enough to resolve the debt crisis if its leaders have the political will to act.

The economy in the 17-nation bloc that uses the euro has all but stalled, with some analysts saying it has already dipped into a recession. The European Central Bank took a modest step ahead of the summit to boost lending, trimming its prime interest rate a quarter percentage point to one percent, the second cut in two months.

German Chancellor Angela Merkel and French President Nicolas Sarkozy are calling for the eurozone nations to curb excessive spending and impose strict penalties on violators. Their plan would also create a unified corporate tax rate and a new financial transaction tax.