There are growing expectations in financial markets that the ECB will have to ride to the rescue again with Spain under intense pressure, the Dutch government having collapsed over budget plans and latest data showing the euro zone is being driven back into recession.

The message from the currency bloc's central bankers is very different - having created more than a trillion euros of low-cast, three-year money via so-called LTROs to avert a credit crunch, time has been bought for governments and banks to cut debt and clean up balance sheets, they have consistently said in recent weeks.

Draghi, while sounding less emphatic than colleagues such as Bundesbank chief Jens Weidmann, stuck close to that line in an address to the European Parliament's economic committee.

"The primary mandate of the ECB is ensuring price stability in the medium term for the whole of the euro area. I think that we have to ... (keep) this thin but delicate balance where we want to preserve the credibility of the ECB," Draghi said.

However, he added that any "exit strategy" from the ECB's emergency measures, something Weidmann and others have said should be discussed, was premature given prevailing conditions.

He said banks must strengthen their finances further, including by retaining earning and bonus payments, while the ECB had played its part in buying governments time.

"Our LTROsboth have been quite timely and successful. If the only thing we had achieved is to buy time, which by the way is not the only thing we achieved, we would have been successful. I think buying time is not a minor achievement," Draghi said.

The euro zone's business slump deepened at a far faster pace than expected in April, data showed on Monday, suggesting the economy will stay in recession at least until the second half of the year.

Draghi conceded recent data had been mixed though he expected overseas demand and the ECB's still very low interest rates to support growth.

"At the same time, downside risks relate in particular to a renewed intensification of tensions in euro area sovereign debt markets and their potential spillover to the real economy," he said.

Despite the political stand-off in the Netherlands, the immediate pressure is off. Spanish and Italian 10-year government bond yields fell on Wednesday and are both comfortably below the 6 percent mark which starts to flash danger signals.

ECB Executive Board Member Jose Manuel Gonzalez-Paramo said Spain would not find it hard to meet its financing needs for the rest of the year despite rising borrowing costs.

Madrid has already met 50 percent of its planned issuance in medium and long-term bonds for the year, and the ECB policymaker said in an interview published in Expansion newspaper on Wednesday it would complete its plans well before year-end.

Other euro zone central bankers added to the drumbeat of comments suggesting the ECB is in no mood yet to create more long-term money for banks, let alone resume its government bond-buying program, which has essentially been inactive for the past 10 weeks.

Draghi said the bond-buying scheme was "neither eternal nor infinite" while Bundesbank board member Andreas Dombret said banks should not rely on the ECB providing unlimited liquidity as an alternative to adjusting their business practices as the policy will be removed before it creates risks to financial stability.

Socialist Francois Hollande, favorite to take the French presidency next month, has called for the ECB's mandate to be revised to add a responsibility for promoting growth.

Draghi insisted the ECB's primary mandate was to ensure price stability and had to remain so.

(Writing by Mike Peacock. Editing by Jeremy Gaunt.)

• A Permanent Economic Emergency