Brussels: European Union (EU) leaders took a big stride towards establishing a single banking supervisor for the euro zone, agreeing it would enter into force next year, opening the way for the bloc’s rescue fund to inject capital directly into ailing banks.

European Council President Herman Van Rompuy said the 27 leaders agreed at a Brussels summit to adopt a legal framework by the end of this year giving the European Central Bank (ECB) overall responsibility for banking supervision.

“Once this is agreed, the single supervisory mechanism could probably be effectively operational in the course of 2013," he told a news conference after nearly 10 hours of talks.

French and EU officials said all 6,000 banks in the single currency area would gradually come under ECB supervision by 2014, starting with banks receiving state aid, then large cross-border institutions. Most day-to-day oversight would be delegated to national bodies.

Creating an effective banking union, for which this deal was a first step, is regarded by the International Monetary Fund (IMF) and market economists as a key component in overcoming the euro zone’s three-year-old debt crisis.

French President Francois Hollande said the leaders did not discuss possible financial assistance for Spain, but he laid out a series of steps that could turn a corner in the crisis.

“Tonight, I have the confirmation that the worst is behind us," he told a 3am news conference.

“We are on track to solve the problems that for too long have been paralysing the euro zone and made it vulnerable.

“If the December European summit confirms the decisions we took, if Greece finds a lasting solution, if Spain recovers funding mechanisms, then we will be done with a situation which weighed on markets and on the confidence in the euro zone."

German Chancellor Angela Merkel said it would take more than a couple of months before the supervisor was fully effective and direct bank recapitalization could be considered.

However, the agreement appeared to be a defeat for German finance minister Wolfgang Schaeuble’s efforts to delay and limit the scope of European banking supervision.

Germany has been reluctant to see its politically sensitive savings and cooperative banks come under outside supervision. It rejects any joint deposit guarantee under which richer countries might have to underwrite banks in poorer states.

The deal came after the leaders of France and Germany, Europe’s central powers, held a private meeting after clashing in public over greater EU control of national budgets.

The point when ECB will effectively become the bloc’s banking supervisor is important because it would open the way for the euro zone’s bailout fund to inject capital directly into troubled banks, without adding to their host governments’ debts.

A French government source said the European Stability Mechanism (ESM) could start recapitalizing troubled banks as early as the first quarter of 2013, but a German source said it was “very unlikely" to happen so soon.

Merkel earlier demanded stronger authority for the executive European Commission to veto national budgets that breach EU rules. She said a December EU summit would take decisions on these issues of closer euro zone economic governance.

For once, the summit was not under intense pressure from financial markets, which have calmed since ECB pledged last month to intervene decisively if needed to buy bonds of troubled euro zone states to preserve the euro.

“Fiscal capacity"

The EU leaders issued a statement welcoming Greece’s progress towards an agreement with its lenders and saying good progress had been made in putting the bailout back on track.

In Athens, police clashed with protesters hurling stones and petrol bombs during a general strike that brought much of the near-bankrupt country to a standstill.

Merkel also advocated the creation of a European fund to invest in specific projects in member states which she said could be fuelled by a financial transaction tax which 11 euro zone countries have said they will adopt.

Her call echoed a proposal for the 17-member euro zone to have its own budget—known in EU jargon as a “fiscal capacity"—on top of the 27-nation union’s common budget, which mostly funds agriculture and aid to poorer regions.

Several states, including the Netherlands, Finland and Austria, were uneasy at the idea but none rejected it outright.

Since ECB said last month it was ready to buy the bonds of struggling euro zone states in unlimited amounts, state borrowing costs have fallen sharply, easing the immediate pressure for Spain to seek a bailout.

Spain’s 10-year bond yields sank to their lowest since February at an auction on Thursday, helped by Moody’s decision this week to leave its credit rating at investment grade.

But rather than signalling that Madrid does not need help, Moody’s verdict was predicated on Spain soon applying for a euro zone assistance programme to trigger ECB intervention.

Italy raised a bumper €18 billion from a four-year inflation-linked retail bond—the most ever raised in a single debt offering in European markets—reducing its need to issue debt before the end of this year.

On the banking union, much work remains to be done and the deeper the discussion union goes, the more complex and problematic it will get.

Countries outside the euro zone—particularly Britain, which has Europe’s biggest banking sector—are concerned their banks could be disadvantaged if a balance is not maintained between ECB and its oversight of euro zone banks and the powers of other authorities to oversee non-euro zone banks.

And if non-euro zone countries such as Poland join the banking union, as policymakers are hoping, it is unclear what representation they would have within ECB, since the central bank is currently answerable only to euro zone member states.