Bill Murray is to star in 'Ghostbusters 3'.

The 64-year-old actor - who starred in the two earlier movies in the franchise, in 1984 and 1989 - is set to appear in the eagerly-awaited Paul Feig-directed reboot, having been spotted by The Hollywood Reporter on the set of the new movie.

Bill had previously distanced himself from the reboot, telling chat show host David Letterman earlier this year that his reluctance was linked to the second 'Ghostbusters' movie being less well received than the original.

However, it appears the Hollywood icon has backtracked and is set to star alongside Melissa McCarthy, Kristen Wiig, Kate McKinnon, Leslie Jones and Chris Hemsworth in the movie, which is due out next year.

In June, meanwhile, Emma Stone admitted she declined the chance to appear in the film because it was too ''big'' a commitment.

The 26-year-old actress revealed that although she really liked the script, the timing wasn't quite right.

She said: ''The script was really funny. It just didn't feel like the right time for me.

''A franchise is a big commitment - it's a whole thing. I think maybe I need a minute before I dive back into that water.''