Yesterday morning the ECB and Europe's national central banks went into the foreign exchange market and bought euros. Unlike the previous occasion on September 22nd they did it without the backing of the other major international central banks.

The move was initially well received and the currency rallied by almost two cents. It was said Mr Duisenberg had made amends for his gaffe of a few weeks ago when he told the Times newspaper that further intervention was unlikely. But by mid-afternoon the currency was actually below the level at which intervention had taken place.

According to Mr Stephan Monissen of Schroder Salomon Smith Barney, the unilateral action meant the market took it less seriously. "The ECB said it did not ask the others to join. However, this suggests that the ECB did not expect the others to agree to help. But, rather than a sign that the US is not interested in a higher euro, it may be that the US administration feels reluctant to act just a few days ahead of the US presidential election. Given this special situation, the lack of support may not be as negative for the euro as usual."

Investors also took heart from early comments from the finance ministries in Germany and France. The German Finance Ministry spokesman said it would "leave any commentary to the ECB itself. The one thing I can tell you is that a strong euro is in our interest." French finance minister Mr Laurent Fabius said he had been informed and fully approved the move. But as Mr Colin Hunt, chief economist at Goodbody Stockbrokers pointed out, the idea that Europe would speak with one voice had been voided by the end of the day when German finance minister, Mr Hans Eichel, and Bundesbank president, Mr Ernest Welteke, came out with so-called supportive comments.

According to Mr Welteke, the euro could have already bottomed out and he added he was pleased with the level it reached after the currency intervention.

But overall it seems the market had simply changed its mind - the intervention was simply not worth as much when it was a unilateral move from the ECB. At the end of the day the currency was at the same level as the day previous. As one wag remarked, Mr Duisenberg is just like the Grand Old Duke of York - he marched the euro up the hill only to let it fall back again.

Nevertheless, this latest round of buying was probably not wasted. It is not yet clear how much it cost, but it should put a floor under the currency's value at around $0.86. It has been rising for several days as US data pointed to a soft landing in that economy.

Wisely the ECB chose to reinforce that trend. It was unfortunate that it could not persuade the other central banks to join in. It is not clear if this was because of the proximity of the US general election or the reported reluctance of the US Treasury Secretary, Mr Larry Summers, to support the euro - believing it has further to fall.

Investors are now likely to continue testing the willingness of the ECB to step in again. Much will depend on tone of data releases over the coming week.

For now the US economy appears to be slowing and fears of further rate hikes in the US are giving way to expectations of a cut in the early months of next year, according to Mr Colin Hunt, chief economist at Goodbody Stockbrokers.

Because of the shifting growth and interest rate outlook in Europe and the US, the dollar is losing some of its attractiveness and there is a greater interest in the euro. And according to Mr Hunt, it is probably fair to say that the euro's days are behind it. "The markets are not eager to press it higher but what should happen is a gentle appreciation unless the ECB delivers concerted intervention which could drive it higher more quickly," he said.