President Barack Obama said he welcomed recent declarations by European leaders and the ECB on the need to do whatever is necessary to preserve the euro.

U.S. Treasury Secretary Timothy Geithner had a blunter message for the euro zone, saying it must take steps including "bringing down interest rates in the countries that are reforming and making sure those banking systems can provide the credit those economies need".

Obama, in a telephone call with French President Francois Hollande on Wednesday, "encouraged their efforts to take decisive action", the White House said.

Hollande reassured Obama that European Union member states aimed to enact soon the decisions taken at a summit in late June, according to the French leader's office.

Germany, whose voters are deeply hostile to funding bailouts of the euro zone's weakest members, agreed in principle at the summit that the bloc's rescue funds could buy bonds of countries that are struggling to borrow on international markets.

Geither made his more forthright comments in an interview with Bloomberg Television recorded on Tuesday, a day after he flew to Germany to meet Finance Minister Wolfgang Schaeuble and ECB President Mario Draghi.

Italy and Spain, the euro zone's third and fourth largest economies, are struggling to fund their budget deficits and debt obligations at affordable levels as bond market investors take fright.

Draghi's promise last week to do whatever it takes to preserve the euro, within the ECB's mandate, stirred speculation that its Governing Council might take more radical steps at a monthly policy meeting on Thursday.

"BOLD AND APPROPRIATE"

Italian Prime Minister Mario Monti said Draghi's promise was "bold and appropriate", and said European leaders were weighing joint intervention by the ECB and the euro zone's rescue funds.

He predicted that the future permanent rescue fund, the European Stability Mechanism (ESM), would "in due course" be granted a banking licence so it could tap ECB funds to buy almost unlimited amounts of bonds despite German opposition.

Market expectations of a major ECB move this week have faded somewhat. Those traders and investors who expect action on Thursday would sell the euro and European shares, and drive up Spanish and Italian bond yields if the ECB sits on its hands.

Geithner said Schaeuble and Draghi had told him of plans they were making on tackling the crisis, but he cautioned against expecting immediate action.

Past crises showed that the longer it took to address the issues, the more they cost. "I believe they understand that. That's why they've signalled they are prepared to move further. Now again, this is going to take time," Geithner added.

German Vice-Chancellor Philipp Roesler rejected pressure for the ECB to step in and cap the borrowing costs of countries in trouble, saying the central bank should stick to fighting inflation and not ease market incentives for reform.

"If you take away the interest rate pressure on individual states, you also take away the pressure on them to reform," Roesler, economy minister and leader of the Free Democrats, junior partners in Chancellor Angela Merkel's centre-right coalition, told reporters in Berlin.

He also reasserted Germany's firm opposition to letting the ESM borrow from the central bank, calling this "the road to an inflation union".

Nick Parsons, head of markets strategy at nabCapital in London, said the euro could fall a couple of U.S. cents from current levels, while bond market analysts expect Spanish yields to reach new euro-era highs if the ECB does not act.

At the heart of the crisis, Greek political leaders said on Wednesday they had reached agreement on 11.5 billion euros of austerity cuts demanded by the country's lenders. Failure to agree the cuts threatened a sequence of events that could have led to Greece's exit from the single currency.

The head of one of its lenders, Christine Lagarde at the International Monetary Fund, promised to stand by the country and "never leave the negotiating table", while calling on its leaders to do more with structural reforms and by improving tax collection.

She also warned that uncertainty over the future of the euro zone was clouding the horizon for the Spanish economy.

MONTI ON TOUR

Monti, who is touring Europe to press for action to bring down Rome's borrowing costs, made his pitch to euro zone hardliner Finland on Wednesday, saying Italy did not need an assistance programme but might in future need "a breathing break" from high interest rates.

"We have in mind a possible intervention through EFSF, ESM and the ECB," Monti was quoted as saying by Finnish daily Helsingin Sanomat before he met Prime Minister Jyrki Katainen.

Central bank sources have told Reuters that intervention could be at least five weeks away because Draghi's comments had not been agreed in advance with the Governing Council, and other elements must first fall into place.

The sources said the ECB could revive its mothballed programme of buying the bonds of troubled governments along with the rescue funds, but Spain would first have to request assistance, which it has resisted so far.

Credit ratings agency Standard & Poor's affirmed Spain's sovereign BBB+/A-2 rating on Wednesday, citing its commitment to economic and fiscal adjustments, but warned it risks losing investment grade if euro zone support fails to boost confidence.

Euro zone leaders would have to agree to the rescue funds buying up government bonds, and the German Constitutional Court would have to uphold the legality of the bloc's permanent rescue fund in a ruling due on September 12.

The leaders have spent the past week issuing statements promising to take whatever steps are necessary to rescue the currency, but none has raised expectations as high as Draghi, who heads the only federal European institution able to act swiftly and decisively.

However, the ECB is divided, with Germany's Bundesbank opposed to reviving government bonds or giving the euro zone rescue fund a banking licence.

Draghi met Bundesbank chief Jens Weidmann privately earlier on Monday to try to reconcile differences on what action the bank might take. Neither bank would comment on the meeting.

The Bundesbank released on Wednesday a June 29 interview for an in-house publication in which Weidmann said governments expected too much from the central bank, and what they wanted did not always make economic sense.

"Politicians overestimate the central bank's capacity and place too many demands of it," he said. "Whether it's about interest rates or any sort of special measures, in the end it always comes down to the same thing: trying to rope the central bank into meeting fiscal policy objectives.

Weidmann said the Bundesbank would continue to defend its positions firmly "so that the (European) monetary union remains a stability union".

With the economy slowing and inflation under control, other options on the ECB's radar screen include a possible further cut in interest rates and a further loosening of rules on the collateral it will accept to lend funds to banks.

(Additional reporting by Terhi Kinnunen in Helsinki, Swaha Pattanaik and Richard Hubbard in London, Eva Kuehnen in Frankfurt and Margaret Chadbourn in Washington; Writing by Paul Taylor; editing by Will Waterman and David Stamp)

• A Permanent Economic Emergency