If the IMF has already secured a promised backstop from the U.S. then Mme. Lagarde has every reason to be confident that no further reserves are necessary. The Fed has already established a precedent of unilaterally offering swap lines to foreign banks, which amounted to $16T worth of loan guarantees during the last round of this crisis. On the other hand, if European political leaders think that tighter vertical EU integration will be the deus ex machina needed, they must know that it will not fit this timeline. One week is not enough time to both forge a revised EU constitution and ramrod it through every member state's parliament.
The most probable result of next week's action will be another toothless agreement in principle, followed by noncompliance from the PIIGS and immediate sovereign debt downgrades. We will then see whether the IMF activates its pre-existing swap lines with the Fed, and whether those loans stay locked into Eurpean banks' reserve requirements as non-hyperinflationary balance sheet decorations.