Tony Blair a 'Simpsons' guest star
(CNN) -- British Prime Minister Tony Blair lends his voice to "The Simpsons" in a new episode airing this week.
Fox has been running promotional ads for the episode, in which Homer takes Marge and the kids on a trip to London, at one point ramming a car through the gates of Buckingham Palace and upending the queen's horse-drawn carriage.
Over the years, hundreds of celebrities have visited Homer, Marge, Lisa, Bart and Maggie Simpson in their hometown of Springfield.
"The Simpsons," now in its 15th season, holds the title for "Most Celebrities Featured in an Animation series" in the Guinness Book of World Records. By the time its contract is concluded -- in spring 2005 -- the show will also claim the record for the longest-running sitcom ever, besting "The Adventures of Ozzie & Harriet."
With his appearance this week, Blair joins such celebrity guest stars as Magic Johnson, David Hyde Pierce, Kelsey Grammer, Paul and his late first wife Linda McCartney, Meryl Streep, Aerosmith, Jack Lemmon, Mel Gibson and Britney Spears.
A spokesman in Blair's press office told CNN the prime minister taped the voiceover in April, at the height of the Iraq war.
He said Blair is a big fan of "The Simpsons" and likes to watch the show with his three teenage children.
In the episode, Blair meets the Simpsons at London's Heathrow Airport and invites them for tea at his official residence, No. 10 Downing Street.
After getting advice from Blair on where to visit in London, Homer causes chaos by tipping tea from his Union Jack cup over the carpet. He ends up locked in the Tower of London.
The episode is entitled "The Regina Monologues" -- a play on the Latin for queen and the theater production "The Vagina Monologues."
The show, which also features the voice of "Harry Potter" author J.K. Rowling, aired Sunday in the United States and will air in Britain in January.