Tony Blair is to appear in the American cult cartoon show The Simpsons.
Mr Blair is believed to be a big Simpsons fan
The prime minister recorded three lines of dialogue for an episode in which he gives the dysfunctional Simpson family a few tourism tips as they holiday in the UK.
"He was approached by the programme some time ago and asked whether he wanted to appear. It was an opportunity for him to promote the UK tourism industry," a Downing Street spokesman told BBC News Online.
The prime minister is also reportedly a big a fan of the show.
But the timing of his participation in the episode provisionally titled the "Regina Monologues" has been criticised because of the war in Iraq.
The prime minister reportedly recorded the piece on Friday after attending a passing-out parade of young cadets at Sandhurst military academy.
"This is something that has been in the diary for a long time. The programme makers were in the UK to make the episode. It took up a short amount of time," the spokesman added.
THE SIMPSONS GUEST LIST
Sir Ian McKellen
But others think the appearance could boost the leader's reputation.
"The Simpsons are still popular the world over... it will probably do his credibility the world of good," cartoonist Steve Marchant told the BBC.
"He will be remembered for being in The Simpsons long after people remember the war in Iraq. It could be the apex of his career," wrote one newspaper columnist.
A string of famous people have appeared on the show, including former United States presidents Bill Clinton, George Bush and Jimmy Carter.
Harry Potter author JK Rowling will also make a guest appearance on the show.
The Simpsons reportedly bump into the author outside a bookshop where they talk about Harry Potter.
However, footballer David Beckham missed out on being in the show as producers thought he was not famous enough.
The Simpsons, featuring beer-guzzling, doughnut-chomping family man Homer Simpson, his blue-haired wife Marge and kids, Bart, Lisa and Maggie, remains one of the most watched TV shows in the United States and elsewhere around the world after more than 10 years on air.