Analysis By Nick Assinder BBC News Online political correspondent

Just as Tony Blair created the COBRA committee to handle the foot and mouth crisis, so he has taken operational control of immigration.

Alternatively, of course, the whole thing could be viewed by the opposition as a stunt aimed at suggesting something - anything - is being done.

Blair needs to walk difficult line on migration

The obvious questions then are about why things were not already being done, and why Home Secretary David Blunkett wasn't doing them.

The prime minister's spokesman summed up the meeting as a "stock taking" exercise which would: "identify the problems and concerns, define those concerns and produce a work programme which can be considered at future regular meetings to be chaired by the prime minister."

Meanwhile, of course, it is stressed this is no reflection on the home secretary's competence or ability to get a grip on the problem.

The problem

And, if anyone doubted the seriousness of the prime minister's intentions, he has ordered members of the security services to be in attendance.

There will undoubtedly be announcements following the meeting, aimed at showing that ministers really do have the measure of the problem and are acting to tackle it.

Blunkett retains lead role

But what, precisely, is "the problem"?

For the government, what it most definitely is not is the issue of immigration, or managed migration, as a whole.

Indeed, Mr Blair is adamant he is not about to pander to what he believes is a right-wing, anti-immigration or even racist agenda on this - something he appears to believe the opposition is in danger of doing, albeit unwittingly.

And his spokesmen have gone out of their way to stress the problem is the relatively limited issue of abuses of the system.

"The prime minister is determined not to allow abuses of the system to poison the whole idea of managed migration which brings enormous benefits to the whole country," his spokesman has said.

Badly shaken

And Downing Street is pointing to figures showing that immigrants contribute more to society than they take out and stressing that managed migration is overwhelmingly "a good thing".

But the government has been badly shaken by the latest revelations which resulted in the resignation of immigration minister Beverley Hughes.

Rightly or wrongly, the impression has been given that ministers do not have control of the system. It is that impression this summit is aimed at dispelling.

The summit will need to come up with practical moves to tackle the abuses while, at the same time, avoiding fanning anti-immigration flames.

But it is a difficult tightrope to walk. There is a genuine concern about the issue amongst voters which, while ministers believe it is often misplaced, can be a powerful electoral factor.

They believe that the whole issue of immigration is being blown out of proportion in what could prove a highly dangerous fashion.

Yet there clearly have been abuses and the opposition appears to be making political advances as a result.

The summit will need to come up with practical moves to tackle the abuses while, at the same time, avoiding fanning anti-immigration flames.

Similarly it is likely there will now be a concerted attempt by the government to get the facts out on immigration in an attempt to counter the more dangerous, negative campaigns which seem to be gaining ground.

And for many, that will be one positive development from this whole affair.