Hollywood director Steven Spielberg has confirmed that he is working on the fourth instalment of "Jurassic Park" and that the sequel will be an improvement from the last one, which was released in 2001.

"The screenplay is being written right now by Mark Protosevich. I'm hoping that will come out in the next couple of years. We have a good story. We have a better story for IV than we had for III, " contactmusic. com quoted the 64-year-old as saying.

Based on the best-selling Michael Crichton novel, "Jurassic Park" was a cult in itself and went on to gross $350 million in the US when released in 1993.

Starring Sam Neill and Jeff Goldblum, the movie spawned two sequels.