Charles Dallara, head of the Institute of International Finance, wrote up a to-do list for the Eurozone this past Friday. Item One urges the EU to guarantee savers’ deposits in banks and allow time for growth.

In particular, he’s worried about banks in Greece and Spain, which have been weakened by heavy withdrawals. Dallara stresses a Greek exit would cause world markets to suffer.

Read: Greece lighting strikes again

He told Il Sole 24 Ore newspaper, “It’s a mistake to think that an exit by Greece wouldn’t have a very serious effect on the European banks, on the ECB, and on countries like Italy, Spain and Portugal due to contagion. It would destabilize the whole world economy.”

Read more on how austerity measures need to be relaxed.