Kelly made the announcement at his weekly press conference on Monday.
Foles has not played since getting hurt in the second quarter of a Week 9 victory over the Houston Texans. He hurt his collarbone when he was sacked by Texans linebacker Whitney Mercilus. He was originally supposed to miss 6-8 weeks with the injury.
Mark Sanchez has started the last six games for the Eagles. Philadelphia is 3-3 in those games. Sanchez has thrown for 1,752 yards with 10 touchdowns and nine interceptions.
Philadelphia (9-5) is one game back of the Dallas Cowboys in the NFC East after losing 38-27 at home on Sunday night to Dallas.
The Eagles play the Washington Redskins on Saturday.
- Scooby Axson