The fourth Bourne movie will not star Matt Damon but instead focus on a new character played by Jeremy Renner.
Stiles appeared in all of the films in the original Bourne trilogy as Nicky Parsons, but is unlikely to reprise her role in The Bourne Legacy.
"I would love to," she told Digital Spy. "But I don't think there's a part for me."
In addition to Damon, franchise director Paul Greengrass will also not return, with Tony Gilroy taking over to helm the project.
Stiles added: "I'm excited to see it. I think Jeremy Renner is a terrific actor, and Tony Gilroy is a talented director and writer, so I look forward to seeing it."
The actress recently signed up to star in dark comedy Between Us with Melissa George and Taye Diggs.
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