By Nick Assinder BBC News Online political correspondent

Another day, another euro story.

This time we are being told that Tony and Gordon are actively considering delaying a referendum on the single currency until after the next election.

Blair sees the pitfalls

Surely it couldn't be the pivotal intervention of celebrities like Vic Reeves, Bob Geldof and Rik Mayall that have turned the government's head?

Apparently not. It is the unsurprising recognition of the fact that they might actually lose a referendum this side of the poll.

And it makes perfect sense to delay the referendum until it is winnable and, additionally, take advantage of the fact that the Tories would not be able to resist scrapping over the issue again during the election campaign.

End of the world

The trouble with these stories - well-sourced as they mostly are - is that they come and go like predictions about the end of the world.

One minute there's a massive euro-shaped asteroid heading directly towards the planet and heralding Armageddon.

The next we are told it's all tosh and that we can breath easy for the next few million years.

The only certainty in this scenario, of course, is the inevitability of the day or reckoning. It will certainly happen, all we are arguing about is the date.

Many think the same argument holds true about the euro - barring, of course, a Tory victory at the next election.

But, leaving science-fiction to one side, the reality is that the government is positively encouraging this debate.

Trains of thought

There is absolutely no reason to believe the majority of these conflicting stories are untrue, even if they appear in newspapers with a well-known agenda on the single currency.

What they represent is the different trains of thought currently being explored by ministers.

Brown's reputation on the line

It is quite likely that the prime minister and the Chancellor have not yet come to a final decision on the euro referendum.

There would be clear advantages in holding it soon, and certainly well before the next general election, and as long as a "yes" vote is likely.

There are equally powerful arguments about why delay would be strategically astute.

And, frankly, the latest story is only stating the obvious.

Famous five

But, at the moment, there is only one fact at the centre of all this - Tony and Gordon will only hold a referendum when they are pretty certain they are going to win a "yes" vote.

The five tests

Convergence Flexibility Investment Impact on the City Jobs and growth

If the Chancellor's famous five tests are met - and, thanks to their flexible nature, we will pretty much have to take his word on that one - the government will then face the real decision.

And it is the purely political one of whether or not the time is right to go for it.

There certainly will not be a referendum with the government urging people to say "no", whatever judgement Mr Brown comes to over his tests.

Indeed, what many suspect is that the five tests are simply a smokescreen to divert attention while the government takes the political decision.

Political jitters

In other words, never mind the five tests, look at the opinion polls.

The Chancellor is understandably eager to dismiss such talk. And he does have a reputation at stake here, so he will want to get it right.

If Britain enters the euro and it all goes horribly wrong the consequences for New Labour and all who sail with her will be catastrophic.

Maybe that is what this is all about after all - a simple case of the political jitters.

One thing is certain, there will soon be new reports that the government is ready to go for it next Spring.