Cherie to tour the US

Cherie Blair is to make a lucrative lecture tour of the US after being signed up by the world's leading after-dinner speaking agency.

A spokeswoman for the Prime Minister's wife confirmed today that she is being represented by the Harry Walker Agency.

The firm's star clients such as Bill Clinton and Henry Kissinger can command fees of as much as £160,000 a time. U2 singer Bono is also on the agency's books.

Mrs Blair is available for hire as a guest speaker when she visits the US this October in an unprecedented move for the spouse of a serving premier. Her links to the New York agency emerged in a leaked email sent to potential clients.

The message reads: "I have exciting news. Cherie Blair, noted British attorney, human rights advocate and the wife of Prime Minister Tony Blair, has agreed to speak under our auspices this fall for a limited number of engagements."

The email says that Mrs Blair is available on 26, 27, and 29 October and comes with a "value for money" guarantee.

The message continues: " I know Cherie Blair would be a great success at your next event, so please contact me today for more information about her lecture topics, October schedule and future scheduling opportunities."

It goes on to quote Mr Blair saying that his wife "is an enormous source of strength and an extraordinary person in her own right. I never know how she manages with all the different things she does, the work, the family".

Downing Street refused to comment but Mrs Blair's Matrix Chambers issued a statement on her behalf. It said: "Cherie is already speaking in the US in October and that has been in the diary for some time. She has accepted an invitation from this agency to speak while she is there, on subjects which are within her professional expertise."

Mrs Blair has given occasional lectures in Britain, often on a charitable basis.

Using her professional name of Cherie Booth, her website at Matrix stresses that she specialises in human rights and public law. Called to the Bar in 1976, she was made a QC in 1995. She is paid £125,000 a year and sits as a part-time recorder in the county court and crown court.

She has in the past hit the headlines with speeches to the British Institute of Human Rights and on children's rights for Barnardo's.

But the decision to sign up with a leading agency such as Harry Walker may attract controversy given the firm's huge fees.

The move may even trigger fresh speculation that Mr Blair is preparing to leave Downing Street this autumn as it is unheard of for the wife of a sitting Prime Minister to be available for hire in this way.

The Harry Walker Agency was unavailable for comment. Mrs Blair has yet to feature on the agency's list of advertised top speakers.

It is unlikely that she will be able to attract the highest fees but she may command fees in excess of £27,500 per lecture given her status as Mr Blair's wife.