Leaders are racing against the clock to find a solution for Europe's massive debt crisis. But it's an uphill battle.

European Union and eurozone officials called off Wednesday's meeting with finance ministers on finalizing a plan to strengthen European economies against the deepening debt crisis.

The ministers had hoped to announce the plan prior to today's summit meeting.

But leaders cannot agree on two key elements: reducing Greece's debts and strengthening Europe's bailout fund.

Meanwhile, former Federal Reserve Chairman Alan Greenspan warned that as long as there is a divide between the northern and southern countries in the EU, the financial crisis will only deepen.

"The effect of the divergent cultures in the eurozone has been grossly underestimated," he told CNBC.

"The only way to have several currencies from divergent nations lumped together is if they are culturally close, such as Germany, the Netherlands, and Austria," the former Fed chief said.

"If they aren't, it simply can't continue to work," he added.