By Nick Assinder BBC News Online political correspondent

With friends like Peter Foster, Cherie Blair does not need enemies. But she probably knows that by now.

In a statement which, on the surface, appeared designed to support Mrs Blair's version of events surrounding her dealings with him he, in effect, accused her of continuing to tell untruths.

After insisting she had done nothing improper, he went on to flatly contradict her on two key issues.

Cherie's phone calls questioned

He insisted he had spoken to her personally three times on the phone. She has insisted time and again that she only met him once, by accident, and spoke to his solicitors in a conference call on one occasion.

Downing Street has specifically denied she spoke to him more than twice.

Meet the Blairs

Secondly, he claimed she had offered him her "innocent advice" and a "professional view of where he stood" on his deportation case. She has insisted she never gave him such advice.

These may seem like minor details, but not to those who on numerous occasions have asked those precise questions of Downing Street and been given different answers to those suggested by Mr Foster.

Almost as an aside, he also stated that he had been invited to meet the prime minister and his wife on several occasions and refused. He did not say by whom.

The fact is, however, that this now appears to have boiled down to a simple question of who we should believe.

Does the word of a convicted conman carry more weight than that of the prime minister's wife who has confessed to misleading people just once?

The clear aim of his statement was to paint himself as a man who has been deeply wronged - a similar line to the one taken by Mrs Blair in her personal statement.

Do him down

In his statement, Mr Foster deliberately echoed the words of Downing Street in relation to Mrs Blair, by claiming there has been a campaign of "character assassination" against him.

Foster: character assassination

There was even a touch of the Princess Diana's when he stated it was the "establishment" that was out to do him down.

Exactly who he meant by the establishment is open to debate, but most will read it to mean Downing Street and the media.

But probably the single fact that will most undermine Mr Foster's account by those seeking to rubbish him is his revelation he is writing an autobiography which will give a fuller version of events.

This came after he had previously suggested he was agonising over whether to use his personal statement to "conceal or reveal".

It is all too easy to portray that as the latest attempt by Mr Foster to make money out of this affair by hyping his book beforehand.

At the end of the day, however, Downing Street will probably be breathing a qualified sigh of relief.

Spokesmen will be able to persist with their refusal to offer any more comments on the case, preferring to allow, as they put it, "a convicted conman to focus on his own business".