Juncker announced "good progress" on the credit lines and bank-recapitalization tools. Avoiding the word "leveraging," he said work is under way to scale up the fund's capacity without requiring each country to chip in more.
"We are checking if yes or no we could increase the efficiency of the different instruments," Juncker said. Asked whether the ECB would be tapped to boost the fund's clout, he said: "I don't think that this will be the main avenue of our considerations."
The ministers also smoothed a snag en route to a second Greek package by settling the terms under which collateral will be offered to AAA rated Finland, home to a euro-skeptic movement that catapulted to third place in April elections by opposing further bailouts.
While the party now known as "The Finns" didn't make it into the ruling coalition, it captured the Finnish mood and hardened the stance of new Prime Minister Jyrki Katainen in the euro-rescue bartering.
Under the accord, Greek bonds will be transferred from Greek banks to a trustee, which will sell them and invest the proceeds in AAA rated bonds with maturities of 15 to 30 years.
In exchange for the special treatment, Finland will speed its payments into a planned permanent rescue fund and forego a share of profits from EFSF emergency loans. Collateral wouldn't cover its entire Greek exposure. In the event of default, it couldn't cash in on the collateral until Greece's official loans mature, a wait that might last 30 years.
"It's a complicated financial structure," said EFSF Chief Executive Officer Klaus Regling, who brokered the collateral arrangement. He and Juncker said Finland is the only country likely to take advantage of it.
Regling deserves "the Nobel prize for economics or the Nobel peace prize" for engineering the compromise, Rehn said.