The eurozone must explore the option of enlarging its rescue fund, the European Commission has suggested in a letter to heads of state - but the move has nothing to do with the bailout fears dogging Italy and Spain, a spokeswoman insisted on Thursday, dpa reported.
Commission President Jose Manuel Barroso called for the "rapid re-assessment of all elements related to" the European Financial Stability Fund (EFSF) - and its 2013 successor, the European Stability Mechanism (ESM) - in a new letter to eurozone leaders.
The move is needed to "ensure that they are equipped with the means for dealing with contagious risk," he added.
"When we speak about all elements, it ... may well include size as well," commission spokeswoman Karolina Kottova told reporters in Brussels as the letter was released.
"But it has nothing to do with the specific situation of Italy and Spain," she added. "It is part of ... a message the president is sending about how in general we should work together in preserving the stability in the euro area."
The common currency zone's "credibility" is at stake, an EU official who asked not to be named added.
"What we need to do is restore confidence in the markets and show that we're ready to do whatever is necessary," the official said.
Eurozone leaders have so far steered clear of increasing the 440-billion-euro (627-billion-dollar) EFSF's size, but agreed during a special summit on July 21 to expand its mandate in a bid to calm market worries about the eurozone debt crisis spreading further.
This week nevertheless saw renewed turmoil on the markets - also in the wake of a debt-spurred political crisis in the United States - with yields on Spanish and Italian bonds reaching record levels.
The EFSF has already been used to bail out Ireland and Portugal, and is due to be involved in the second rescue package for Greece. Its lending capacity - as well as that of the 500-billion-euro ESM - would likely not be enough to also fund an Italian or Spanish rescue.
Barroso blamed the market instability on investor "skepticism" about the eurozone being able to contain its debt crisis, despite the "bold decisions" leaders made about the EFSF and Greece's second bailout at last month's summit.
"Markets highlight ... first and foremost, the undisciplined communication and the complexity and incompleteness of the 21st July package," Barroso wrote, calling on national officials to fast-track the steps they must take to implement the summit decisions.
EU experts are currently formulating the legal changes needed to for instance expand the EFSF's mandate, which will then have to be ratified by national parliaments.
The commission's expectation is that they would be called upon to interrupt their summer breaks if needed, officials said.