Prime Minister Tony Blair has joined the row over his wife's involvement with Peter Foster's deportation case, insisting it had been "handled entirely properly".

He made the comments as it emerged Cherie Blair had phoned the solicitors of the convicted fraudster to reassure his girlfriend Carole Caplin there was nothing untoward about the immigration proceedings.

Think about Cherie the woman, the decent woman, who's done nothing wrong

Clare Short

Downing Street has previously said Mrs Blair did not "assist" Mr Foster, who helped her buy two flats, in his legal battle against deportation from the UK.

This point was reiterated by Mr Blair in a letter to Tory leader Iain Duncan Smith, who had queried the role of Home Office officials in that case.

"The Home Office have already made it clear that no political interference has taken place in this case," said Mr Blair.

'Lack of judgement?'

BBC political editor Andrew Marr said that there was no suggestion that Mrs Blair had done anything illegal and had been trying to help her friend and fitness adviser Ms Caplin by calling Mr Foster's solicitors.

But Marr stressed: "She is also the wife of the prime minister.

"Simply by making this call, it doesn't look like good judgement."

Duncan Smith asked Tony Blair to clarify key points

Mr Foster's solicitors said Mrs Blair did take part in a conference call on 22 November, but this was only "to reassure" his girlfriend there was nothing untoward about the immigration proceedings.

The solicitor's statement stresses Mrs Blair "did not intrude into our conduct of the proceedings and for the avoidance of doubt, had no say whatsoever in our choice of representation".

Last week, Mrs Blair said she had not known of Mr Foster's criminal past when she first accepted his offers of help for the flat sale.

Her e-mail correspondence over the flats began in October.

'Gutter stories'

But Downing Street said she stood by her statement that she would have been more "circumspect" had she known of Mr Foster's past.

"At no point did she interfere in the immigration case proceedings. Nor would she," said Number 10.

The call to the solicitors had been "short" and aimed at helping Ms Caplin.

International Development Secretary Clare Short told BBC2's Newsnight programme Mrs Blair had done nothing wrong.

She said: "The whole thing is out of control and it is ridiculous.

"All she did was speak to the lawyers on the phone to check if the case was being handled properly.

"There is nothing wrong with that."

Blind trusts

Mr Duncan Smith suggested that the Ministerial Code of Conduct has been broken because the Blairs' blind trust was used to buy the two flats in Bristol.

Blind trusts were set up so ministers did not know how their money was being invested and could not be accused of impropriety.

The prime minister referred Mr Duncan Smith to what his spokesman had said earlier on Monday, that he had been in consultation with Cabinet Secretary Sir Andrew Turnbull before deciding his own code of ministerial conduct had not been breached by his wife buying the flats.

Peter Foster faces deportation proceedings

The Tory leader also asked if it was true that Alastair Campbell, Downing Street's communications chief, had warned Number 10 that Mrs Blair's associates posed a serious threat to the government's reputation.

Mr Blair replied: "You refer to a statement 'denying there was cause for concern' (about Mrs Blair's associates). No such statement has been issued."

Mrs Blair performed her first official engagement on Monday since the row broke last week as she turned on Downing Street's Christmas lights.

Joking with children from the charity Barnardo's Northern Ireland project, Mrs Blair ignored reporters' questions.

E-mails

Earlier, Downing Street had insisted no rules were broken in the property deal, insisting the code covered share dealings and other areas where the government could be thought to influence the situation, not flats.

The prime minister's official spokesman said: "It would be an Alice in Wonderland situation if a family is not able to release its investments and use the money to purchase a flat."

Mr Blair believes the media should "keep a sense of perspective", especially with looming problems like the disarming of Iraq.

Downing Street's initial denials that Mr Foster had been involved in the flats deal had to be hastily corrected when on Thursday the Daily Mail published e-mail proof of his help.