Europe’s currency union has its roots in the agreement signed in 1992 known as the Maastricht Treaty, which set in motion the rules for creating the euro and for joining the euro zone. A later agreement established the European Central Bank, which manages interest rates much like the United States Federal Reserve.

But the Maastricht Treaty stopped short of telling countries how to handle spending or taxation, leaving them loose rules on budget deficits to follow — or break, as many did, including Germany and France in the early days of the euro.

In the United States, of course, agreements between Congress and the White House on budget measures can be extremely difficult to reach. But the European process is even more arduous. The problems were highlighted Friday when talks between the Europeans, the I.M.F. and Greece were put off because Athens was coming up short in its plans for meeting budget targets. Stock markets promptly fell on the news.

This week, more challenges await. The top court in Germany is scheduled to rule Wednesday on whether it is legal for that country’s leaders to make such an agreement. While it is expected to allow Germany to participate in the bailout, the constitutional court could surprise the experts.

On Thursday, officials in Finland are supposed to make a statement outlining their conditions for approving the deal, which will probably set the pattern for other countries seeking guarantees from Greece that their loans will be paid back.

The heavy lifting involved in approving the new deal for Greece illustrates how difficult it would be to create a European Treasury.

But that has not stopped some officials from calling for moves in that direction. Last month, Angela Merkel, the German chancellor, and Nicolas Sarkozy, the French president, proposed new financial transaction taxes for the euro zone, as well as standards for corporate tax laws, so no country could lure businesses at the expense of others with exceptionally low tax rates. They also proposed that each country enshrine in its constitution rules that would limit deficits, a process that is now under way in Spain, Portugal and elsewhere.