The Greek debt crisis could spread panic in financial markets across Europe and beyond, experts have warned.
There is market talk of a potential global contagion, similar to what happened after the investment bank Lehman Brothers collapsed in 2008, contributing to a deep global recession.
"Greece as an economy is tiny but the danger is contagion and market panic," said David Wyss, chief economist at Standard & Poor's in New York.
"If people get scared that Greece could default, they are going to be scared that Portugal will default and then other countries. Once people panic, they panic about everything. We saw that in the wake of the Lehman Brothers failure."
Markets worldwide have been shaken by a wave of bad news from Europe, starting with a downgrade of Greece's heavy debt load and then downgrades of the debt held by Portugal and Spain.
In Asia, there are not yet significant concerns about the creditworthiness of the region's governments but big economies like China and Japan still have much at stake.
Europe is an important export market for both and their manufacturers are counting on sending ever more goods to the continent. China and Japan are also among the biggest investors in the debt issued by other nations, the US especially, with holdings worth hundreds of billions of dollars.
Meanwhile, European monetary affairs Commissioner Olli Rehn said a European bail-out deal for Greece would give the country a "breathing space" to escape from its spiral of debt.
He said the deal would be concluded within days, to restore stability not just to the Greek economy but to the single currency itself.
"In the past 10 days, the experts of the Commission, the European Central Bank and the International Monetary Fund have worked extremely effectively and hard with the Greek government to work out a programme that will reverse the debt spiral of Greece and restore its overall economic competitiveness," Mr Rehn told a press conference in Brussels.