Animated series The Simpsons is to become the longest-running prime-time show in US TV history after two more seasons were announced.

Currently in its 20th season, the Springfield-set cartoon has matched the record of cowboy drama Gunsmoke and will surpass the landmark when its 21st season begins in the autumn.

Fox has ordered a 22nd season, which will take the total number of Simpsons episodes to 493.

"The popularity of the show all over the world continues and it is gratifying," creator Matt Groening told CNN.

"And the show's still fun to do. That's always been my ultimate deciding factor: Is it still fun? And it is... I get to go in and listen to these brilliant actors make funny lines written by geniuses even funnier.

"It's a totally entertaining experience from my point of view."

The show, which tells of the exploits of Homer, Marge, Bart, Lisa and Maggie Simpson, as well as those of their family, friends and neighbours, has won 24 Emmys in its 20 years on air.

On March 17th, a new episode - In The Name of the Grandfather - will have its premiere in the UK for the first time in the show's history.

27/02/2009 10:36:15