WHAT should an ex-Prime Minister do next after his own MPs have put him out to grass?

That is Tony Blair's dilemma now. Here at Westminster, political reporters are breathless with excitement about our departing leader's future career, even before he finally confirms his retirement today. Many of the reports appear to owe more to a vivid imagination than an exclusive tip-off, but one has the ring of truth - of which, more later.

The leading Blair-baiters in the national media are desperate to portray him as greedy, hence the theory that he will "take the money and run" - off to the lucrative American lecture circuit.

This theory has Mr Blair waving an immediate goodbye to Westminster also to write his memoirs and take up lucrative directorships, pocketing £10m in his first year out of office alone.

It also has him quitting in July as Sedgefield's MP - conveniently allowing his earnings to remain under wraps, because he would not need to declare them in the MPs' register of interests.

However, it is hard to square this scenario with Mr Blair's pledge - voiced through his agent John Burton - that he will only walk out on Sedgefield for a job of "international importance".

Mr Burton suggested the United Nations, which seems somewhat unlikely after Kofi Annan, its former secretary general, branded the Iraq invasion "illegal".

Nevertheless, Mr Blair must surely have something more noble lined up than an autobiography and back-slapping speeches before he hands in his Commons pass prematurely?

Other punts at his prospects - a roving ambassador in Africa and the Middle East, an envoy for George Bush - didn't appear to fit the bill either. After all, how much roving can you do? Furthermore, Mr Blair insists he will do something different - yet many might say he has been working for President Bush for years.

Another scenario had Mr Blair desperately seeking an "executive role", most likely a new post of president of the European Union, but that won't be available until 2009.

There was an offer to become a Hollywood star - playing Terminator Four - but I think Governor Arnold Schwarzenegger was joking.

So how about a suggestion, yesterday, that Mr Blair will set up a global foundation to foster greater understanding between Christians, Jews and Muslims?

Apparently, the Prime Minister believes there is a gaping hole where an "interfaith organisation" should be, fostering religious harmony from Britain to the Middle East. After all, Mr Blair was enthusiastically reading the Koran even before the September 11 attacks and we should never underestimate his belief in his ability - Iraq notwithstanding - to win people over.

I say it has the ring of truth only because of these little-noticed remarks by Education Secretary Alan Johnson, who recently told journalists: "Tony has been doing a lot of reading on theology. He's very interested in theology and I wouldn't be surprised if there was something there he wants to do."

IT took No 10 only a few minutes to rubbish the claim that Mr Blair would also announce today that he was standing down immediately as an MP, so where did it come from?

The word is that the source was a former lobby hack and Labour Party aide with no inside knowledge, but with his eye on the ultra-safe County Durham seat. He won't be the last.