By Nick Assinder BBC News Online political correspondent

Since the day he was elected, prime minister Tony Blair has insisted Northern Ireland is at the top of his political agenda.

And ever since that day in 1997 there has been ample evidence of his sincerity on that.

Blair and Ahern: Battling for the Good Friday agreement

He has devoted a large part of his energies to bolstering and even moving the fragile peace process forward.

It is even suggested that it was only his personal intervention that ensured the Good Friday Agreement became a reality the year after he was elected.

There are those who doubt that - the Northern Ireland Secretary at the time, Mo Mowlam, has things to say about it for a start.

But few doubt that the prime minister is, at worst, determined not to have the peace process unravel on his watch.

Early stage

At best, he is credited with being prepared to risk his own credibility on preserving the peace.

The demands on his attention are probably more pressing than before

But that peace is once again under threat after one of the most serious failings of the process yet.

And again the prime minister has immediately stepped into the crisis at an early stage - and probably long before he can be assured of any political advantage as a result.

But this time, the demands on his attention are probably more pressing than before. Things are crowding in.

There is the looming crisis over Iraq. The UN is taking longer than he clearly hoped to come up with new resolutions on Saddam Hussein.

And he notably failed to get what he wanted from Russian President Putin during his visit to Moscow last week.

Axis of evil

Meanwhile he has to keep a weather eye on the growing backbench revolt over the issue.

North Korea is suddenly in the spotlight

Then there is the wider war against international terrorism which has been sharpened terribly by the Bali atrocity.

With all that on his plate, the prime minister was already facing claims that he simply could not keep his attention properly focussed on both issues.

Now he has been told that North Korea, part of President Bush's axis of evil, is indeed trying to produce nuclear weapons.

That will have to be dealt with and Mr Blair is under intense pressure to declare precisely what he is prepared to do about it.

Why plan to bomb Baghdad and not Pyongyang?

Spinning plates

So having to step into another crisis in Northern Ireland is just about the last thing the prime minister needs at the moment.

Can Stormont's latest crisis be resolved?

And there is clearly huge frustration inside Downing Street at the continuing inability of both sides in Northern Irelands to keep their own house in order.

That may even, on occasion, spill over into anger.

The prime minister knows that he will face more accusations that he cannot possibly keep all these different plates spinning.

And if he fails to execute this juggling act the consequences can only be guessed at.