BRUSSELS — With shares plummeting from China to the United States on fears that Greece's debt disaster could undermine a global recovery, European leaders gathered today for another try at calming panicky markets skeptical of their pronouncements that the crisis won't spread to other countries.

A summit of the 16 leaders from countries using the euro — initially called to sign off on a 110 billion euro bailout package for Greece and draw lessons for the future — faces the challenge of urgent crisis management, after the euro dropped to its lowest level in 14 months and bond markets dumped Greek debt.

EU leaders have insisted for days the Greek financial implosion was a unique combination of bad management, free spending and statistical cheating that doesn't apply to any other eurozone nation, such as troubled Spain or Portugal. They said the bailout should contain the problem by giving Greece three years of support and preventing a default when it has to pay 8.5 billion euros in bonds coming due May 19.

Yet, the markets have taken little heed. Stocks, Greek bonds and the euro plunged even after the head of the European Central Bank, Jean-Claude Trichet, underlined "Portugal is not Greece. Spain is not Greece" on Thursday.

Along with the eurozone meeting, the G-7 finance ministers will hold a teleconference today on the crisis, according to Japan's finance minister.