Leading article: One step on the long road out of the euro crisis

Neither GDP growth nor even a 'big bazooka' bailout fund are enough on their own

After much fanfare, today's EU summit will not live up to its billing after all. Rhetoric from Angela Merkel and Nicolas Sarkozy as recently as last week promised that a "comprehensive solution" to Europe's sovereign debt crisis was just days away. Now, after yet another hiccup, the much-vaunted "global package" to restore calm in the eurozone's gyrating markets will not be finalised until later in the week.

A few more days of negotiations is no cause for panic. After so many months of dithering and denial from EU politicians, any real developments are to be welcomed unreservedly. And all the signs from the first phase of the summit, last Sunday, suggest there will be genuine advances on several crucial issues, albeit slightly later than planned.

There is, finally, an acknowledgement of the fact, long accepted by the markets, that Greece cannot sustain its €350bn debts. Writedowns of anything up to 60 per cent are being negotiated, with exposed banks set to raise an extra €108bn-worth of capital to withstand the shock of the so-called "haircuts". Meanwhile, the European Financial Stability Fund is to be sufficiently expanded so that it can act as a credible backstop against contagion from Greece to other eurozone economies such as Italy and France.

So far, so good. But any suggestion that the crisis can be dealt with so easily is hopelessly premature. Even the new proposals themselves are likely to raise as many questions as they answer. Far from being a "comprehensive solution", they are, at best, a beginning.

That said, the value of a sense of coherent direction from Europe's politicians should not be underestimated. Stock markets stabilised almost immediately at the first hints of an agreement, and have remained relatively steady since. But even if there is evidence that eurozone leaders have grasped the scale of what is at stake – though, sadly, prodded into action by a chorus of international criticism – the challenges ahead are no easier to navigate.

Even if the immediate crisis can be averted, the grinding austerity faced by Greece, even with the debt writedowns, will be no easy task, either politically or economically. And the need for such public pressure on the Italian Prime Minister, Silvio Berlusconi, at last weekend's EU summit only underscores the difficulty in enforcing budget discipline elsewhere in Europe against the grain of domestic political interests. Then there is the issue of growth. What Europe needs more than anything is economic expansion, to help take up the slack from slashed public sector budgets. That means pushing ahead on such thorny issues as the expansion of the single market and efforts to boost competitiveness by cutting excess regulation.

But neither growth, nor even a "big bazooka" bailout fund, will be enough without a solution to the inconsistency at the heart of the euro project. Taken as a whole, the eurozone can more than absorb its sovereign debts. The problem is that lenders to individual governments do not believe that the bloc will stand behind its members. The cavilling of eurozone politicians has not dispelled such fears. But there is no avoiding the issue. Ultimately, the only way to save the euro is to pursue monetary union to its logical conclusion. And that means closer fiscal union.

It is difficult to overstate the implications of such proposals. David Cameron's spat with Mr Sarkozy over Britain's involvement in the now-delayed finance ministers' meeting is just the earliest hint of the shift in power that a "two-speed" Europe would entail. Europe's politicians have, rightly, been lambasted for their dilatory response to the crisis. Any decisive action this week comes not a moment too soon. But it is still only one step on a long and difficult road.